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torstan
06-26-2008, 12:28 PM
So, there is a job thread somewhere in here (looks like it got dropped off the bottom of the page) where I foolishly admitted to being a theoretical particle physicist working on predicting what might be seen at the new collider being built under CERN. If this has no interest to you, feel free to skip to other threads, this one will be unashamedly physicsy. I also promised to post here if there was any major news on the collider.

Well, the short version is this - there is a collider being built under the Swiss-French border. Here's a picture of where it sits and how big it is:
4653

The big white circle shows the path of the tunnel the collider sits in - it's 100m or so beneath the ground and the tunnel has a length of 27km. Note Geneva airport on the right for scale.

The plan is that protons - the nucleus of a hydrogen atom - will be accelerated around the ring to very close to the speed of light in two beams going in opposite directions. Once they are up to speed these beams will then be crossed (with less dramatic consequences than in Ghostbusters - but this is actually what those beams where based on). The beams will collide at two points on either side of the ring and enormous (6 storey tall) detectors will catch the subatomic debris that comes out.

torstan
06-26-2008, 12:37 PM
So, some facts and figures.

The LHC - Large Hadron Collider
(hadrons are composite particles - of which protons and neutrons are two examples. Always be careful when typing hadron not to get the d and r mixed by accident. Easy typo, completely different machine....)

26 659 m in circumference - the largest machine ever built
>10 years to build, and due to start this summer (first collisions predicted in August)
The magnets are kept at 1.9 degrees above absolute zero so they are colder than outer space. This is so they are superconducting.
This requires the world's largest fridge - >10,000 tonnes of liquid nitrogen.
This, combined with the detectors, will produce more than 800,000 GB of data every year and requires a whole new class of supercomputer to be designed to be able to handle it.

This of course is if it works as planned. We'll find that out later this summer.

RPMiller
06-26-2008, 12:41 PM
So you aren't taking the warning to not cross the beams seriously then? ;)

I think this whole project is really interesting. I think my biggest question is what do the participants hope to learn from it? I think that is the one aspect that I still don't quite understand. Will this provide a new energy source? Unlock some important information to improving life? That sort of thing?

torstan
06-26-2008, 12:49 PM
Okay, all very impressive, but didn't someone mention a black hole?

Well yes, one possible result is that the LHC will produce microscopic black holes the size of atoms. This, contrary to popular speculation, would be great. In fact, some theories predict that we should produce them. However, rather than sucking in the world, these would decay in the detector - exploding in a spectacular shower of subatomic particle that would light up the detector like a Christmas tree. I've seen experimental plots of an event like this. People take it very seriously and would be very excitied if it happened.

But, I hear you shout, what if it doesn't decay? What if the black hole sits there, getting larger and larger until it ate the world?

Well, this has been carefully studied. Though we have never created collisions at this energy in a laboratory on earth before, these type of interactions do occur when cosmic rays hit the earth from outer space. So if this was going to happen, it would have done so already. Okay, so maybe we're just lucky that this hasn't happened to us yet? No. It hasn't happened to us, or to Mars, or to Jupiter, or the sun, or any other object we can see. This was addressed in a recent paper (out this week). I think the abstract (or at least the last line of the abstract) is worth a read:

http://arxiv.org/abs/0806.3381

So no, we will not be destroyed by black holes produced at the LHC. The same arguments (that such interactions have taken place in the earth's atmosphere for its entire lifetime and so any bad thing that can happen should have happened already) is a pretty solid argument against all 'LHC will destroy the earth/universe' theories.

On the other hand, humans are a pessimistic bunch and everyone likes to think the scientists will get it wrong, so I believe that there are a number of End of the World parties being organised for early August....

RPMiller
06-26-2008, 12:55 PM
Wouldn't there also be a difference in that the naturally occurring ones do not occur inside of a container that could restrain the event? Does the article say anything about that?

For the record I absolutely do not believe anything bad will happen other than it maybe not working. I am curious about the conspiracy theories though. They always make great roleplaying fodder. :)

jfrazierjr
06-26-2008, 12:57 PM
So, some facts and figures.

The LHC - Large Hadron Collider
(hadrons are composite particles - of which protons and neutrons are two examples. Always be careful when typing hadron not to get the d and r mixed by accident. Easy typo, completely different machine....)
And a totally different tool also. :P



26 659 m in circumference - the largest machine ever built
>10 years to build, and due to start this summer (first collisions predicted in August)
The magnets are kept at 1.9 degrees above absolute zero so they are colder than outer space. This is so they are superconducting.
This requires the world's largest fridge - >10,000 tonnes of liquid nitrogen.
This, combined with the detectors, will produce more than 800,000 GB of data every year and requires a whole new class of supercomputer to be designed to be able to handle it.

Umm so how much energy is this thing supposed to give us? If I got it all wrong, just let me know since I am not very physicy as you put it.



This of course is if it works as planned. We'll find that out later this summer.

Yea... it's this bit that has be worried about the state of the universe after you guys turn this thing on... Typically, anytime some one says "It's completely safe", or "There's no way anything can go wrong", or something like that, the worst possible thing happens.... of course, thats usually in movies, but art imitates life and once in a while life imitates art.:D

Besides, since RPMiller knows the world is going to end in 2012, something will happen to the project and you will have to delay for another 3 years before starting it up again... either that or it takes that long to blow us all to hell, take your pick.

Joe

RPMiller
06-26-2008, 01:01 PM
Besides, since RPMiller knows the world is going to end in 2012, something will happen to the project and you will have to delay for another 3 years before starting it up again... either that or it takes that long to blow us all to hell, take your pick.

ROFLMAO!! This is exactly how conspiracy theories get started. :lol: I love it!

You know the Illuminati are watching and have plans already in motion to make this a reality.

oh and...


FNORD

torstan
06-26-2008, 01:07 PM
Oops, cross-post. Sorry RP.

There are lots of things we hope to learn from this.

1. We expect to understand the origin of mass by finding a particle called the Higgs boson.
2. I personally want to know what dark matter is. There's 5 times more dark matter in the universe than atoms, molecules and all the other stuff we've been studying ever since we started asking questions. We foun out it was there only a few decades ago and there are good reasons to believe that the LHC will be able to produce it from scratch. That would be the first time ever that dark matter was created in the lab on earth. Incidentally, dark matter was the basis for 'dust' in the Dark Materials trilogy (though there's really no basis for thinking it is conscious :) )
3. The LHC will test theories that differ on the number of dimensions we live in - the four we know about (3 space dimensions and one time or N/S, E/W and your heightmap for cartographers) or whether there are another 6 or even seven, and whether they are small or large.
4. It may start to shed light on how the universe began and how it may end, and also whether there are other universes.

These are ordered in degrees of speculation. The first we should definitely answer. The last is highly unlikely to be any more than a hint, if we get that much.

But of course, this doesn't answer your question. Neither of those things is likely to immediately lead to any new technologies that will improve your life. Technologies tend to come when we put research into a field where the theory is already known. Fusion has been understood theoretically for about 60 years, but we'll only get our first working fusion plant in 15 years or so. However the theoretical understanding of fusion came from particle physics experiments - and no-one knew when they started those experiments that fusion might come out the other end. The purpose of these experiments is to find out how the universe works. When we peel back another layer, sometimes we find something that can be turned to our own use, sometimes we don't. The point is that in particle physics, unlike many other sciences, we don't know the underlying theory until we look, so we can't say what use the discoveries may have until they have been made.

That said, the field has a pretty good track record. The straightforward results of the work are things like lasers, tvs, radiotherapy and so on. None of these would exist if we had not researched atomic and subatomic physics.

However more important perhaps are the spin off technologies. The LHC has funneled a huge amount of money into brand new research into superconductors, electronics, seismology, solid state physics and (of course) IT. All of the developments that have been made for the collider will be applied in the rest of the world. Without the collider, much of this research could not be done because it would be way too risky for a company to invest that amount of its own capital into R&D that may not work.

Past examples of spin offs are everywhere, but the most obvious is the Web. That was put in place so that the data from the previous collider at CERN could be shared between the international collaboration of scientists working on this. The LHC has a similar challenge - there will be more data produced than ever before and a computer infrastructure needs to be set up to deal with it, and to handle the processing tasks on this data sample. That requires a supercomputer and we've built something called the Grid (yes, we're no good at names) - a supercomputer that spans the globe that consists of networked computers in universities in countries on every continent. You can submit a job to the Grid and it will use the processing power of computers right across the Grid to do the job. It's the largest distributed computer resource in the world and will eventually be made available to everyone, just like the internet.

Hope that answers that question! Wow, that got a little longer than intended....

NeonKnight
06-26-2008, 01:11 PM
Oooooooo Noooooooooz! Torstan is going to be responsible for creating The Mist in Geneva!

Ooooooo Noooooz!

jfrazierjr
06-26-2008, 01:12 PM
ROFLMAO!! This is exactly how conspiracy theories get started. :lol: I love it!

You know the Illuminati are watching and have plans already in motion to make this a reality.

oh and...


FNORD



Which of course, just brings to mind one of my favorite sayings:
Just because I'm paranoid doesn't mean they're not out to get me.

torstan
06-26-2008, 01:16 PM
@jfrazierjr - This won't give us any energy. Rather we pump energy in to get the particles up to speed and then study the results after they collide. It's like pumping a load of petrol into two trucks, watching the fireball when they collide and then measuring how far the bumper went.

@RP - the protons will collide in a vacuum - the center of the pipe is as empty as the engineers can get it to reduce the chance of them accidentally hitting something other than the proton that is coming the other way. Therefore the collision itself is almost identical to a collision in outer space. In fact, at the atomic scale, even gas is mostly empty, so it's functionally the same as collisions in the atmosphere too, which is where the cosmic ray interactions happen. What happens to the debris afterwards - when it flies off and hits the solid bit, the detectors, is essentially just garbage collection. We pick up the bits and see what happened. So the detector doesn't influence the collision itself. In this way, the collision should be as identical to a collision that occurs outside a detector as possible. Otherwise all we'd be studying was how physics works inside a detector - which wouldn't really help us to understand the wider world :)

jfrazierjr
06-26-2008, 01:18 PM
That requires a supercomputer and we've built something called the Grid (yes, we're no good at names) - a supercomputer that spans the globe that consists of networked computers in universities in countries on every continent. You can submit a job to the Grid and it will use the processing power of computers right across the Grid to do the job. It's the largest distributed computer resource in the world and will eventually be made available to everyone, just like the internet.


AHHH... soooo even if you don't directly blow stuff up in a hugh explosion that rips the fabric of space/time, you will be responsible for building a skynet like entity that will eventually destroy humankind....

Like I said, Torstan destroys the world...:P

Joe

torstan
06-26-2008, 01:19 PM
Anyone read Angels and Demons? I'll support any conspiracy theory that says CERN should have a space plane. That would be cool.

(yes - they have antimatter, no - they could never use it to blow up the Vatican)

@Neon -The Mist? How did you hear about that. That's strictly..... definitely not something I've heard about....

RPMiller
06-26-2008, 01:20 PM
Which of course, just brings to mind one of my favorite sayings:
What are you referring to? That statement came completely out of the blue. ;)

torstan
06-26-2008, 01:21 PM
Well, at least Skynet would run linux (yep - Grid runs linux).

Incidentally there's another collider reference - last terminator had one I think....

jfrazierjr
06-26-2008, 01:22 PM
What are you referring to? That statement came completely out of the blue. ;)


The conspiracy theory bit.

Now... where did I leave my tinfoil hat????

Joe

RPMiller
06-26-2008, 01:24 PM
The conspiracy theory bit.

Now... where did I leave my tinfoil hat????

Joe
Hm... It doesn't appear to be working... Trying again...

FNORD FNORD FNORD

Sir, I think we have someone that is immune. We need a memory erase team stat!

RPMiller
06-26-2008, 01:26 PM
@jfrazierjr - This won't give us any energy. Rather we pump energy in to get the particles up to speed and then study the results after they collide. It's like pumping a load of petrol into two trucks, watching the fireball when they collide and then measuring how far the bumper went.

@RP - the protons will collide in a vacuum - the center of the pipe is as empty as the engineers can get it to reduce the chance of them accidentally hitting something other than the proton that is coming the other way. Therefore the collision itself is almost identical to a collision in outer space. In fact, at the atomic scale, even gas is mostly empty, so it's functionally the same as collisions in the atmosphere too, which is where the cosmic ray interactions happen. What happens to the debris afterwards - when it flies off and hits the solid bit, the detectors, is essentially just garbage collection. We pick up the bits and see what happened. So the detector doesn't influence the collision itself. In this way, the collision should be as identical to a collision that occurs outside a detector as possible. Otherwise all we'd be studying was how physics works inside a detector - which wouldn't really help us to understand the wider world :)
Interesting. I'll be very intrigued to hear about the data collection and the results there of.

Have they given any percentages on chance of success for the whole experiment?

NeonKnight
06-26-2008, 01:29 PM
@Neon -The Mist? How did you hear about that. That's strictly..... definitely not something I've heard about....

When you started talking other dimensions.

OK, I know of the standard 4: length, height, width and time (basicially the previous 3, as in I am the same entity as I was last year but I appear different in the most basic of laymans' terms.)

The 5th dimension and upwards have been theorized as other realities that over lay our own but we just are not in sync with them. This of course then gets into the whole paranormal aspect of that is where the monsters and ghosts and UFOs and what not comefrom.


******WARNING SPOILER INFO BELOW******

In the Steven King novella/and movie The Mist a Military installation was able to open a portal to another dimension and of course that was were all the baddies came from. So, when you mentioned the collider could be used to study the existence of other dimensions beyound the 4 known....

töff
06-26-2008, 01:33 PM
What if the black hole sits there, getting larger and larger until it ate the world?Larry Niven had a story based on the speculation that the Tunguska meteorite was in fact a black hole that went right through the Earth.

I've long been fascinated by particle physics, although I am an utter tyro. Cheers to everybody who's working to expand the collective knowledge of our species!

p.s. Yeh please don't suck the Earth into a black hole, kthnxbai.

Karro
06-26-2008, 01:43 PM
Not having read Mist (or seen the resulting film), I just assumed Torstan was going to give us a map of the array so that others might be able to game out a scenario in which the unpredicted results of these experiments causes tiny tears into extradimensional space, allowing the unspeakable horrors that live beyond our consciousness to slowly leak into our world, which is slowly torn assunder by the unknowable forces at their disposal until, eventually, the entire planet is a ravaged, desiccated husk wherein all of humanity has been consumed by the otherwordly things except those scientists and sundry others still holed up at the CERN facility which, ironically, is the only surviving bastion of life and civilization.

Those last few survivors would be fighting for their lives, struggling to find a way to reverse the flow of extradimensional energy and parasitic intelligence.

I have not played Call of Cthulhu, but it might be best for this game.

I had hoped to include this all in one (maddening) sentence, but, alas, I failed.

torstan
06-26-2008, 01:45 PM
@RPMiller: There's no real chance of the machine 'failing' as such. The Standard Model of particle physics predicts that there is a Higgs boson. If it finds it, Peter Higgs gets a Nobel along worth the experimentalists that find it. If there is no Higgs found, then the entire Model has been disproved - which would be a major result as it would mean that one of the best tested theories ever constructed would be disproved. Finally it could (and is widely expected to) produce a whole world of new matter that we've never seen before, in which case it is champagne all round and a lot of work for me.

The way it could fail is to not actually produce collisions of the energy required, at the rate we need. That would be an engineering failure and is possible, though, we hope, very unlikely. Nevertheless, the collider is scheduled to run for 10 years at least, so even if it doesn't work as expected when it starts, it should be fixed soon enough in that 10 year window. We'll have to wait and see what first runs this summer produce to know how well the machinery is working. Something this large, complex and unwieldy is guarranteed to have teething trouble when they flick the on switch. The question is how serious the problems are and whether they can be fixed before the first physics run next spring (it turns off during the winter because electricity is too expensive and the experimentalists need downtime to tinker).

@Neonknight - There are many theories with extra dimensions, all of which differ on their nature. Every one of them has a good reason why we haven't seen them yet. These generally fall into one of two categories - either atoms can't move in them, but more exotic matter such as gravitons (a hypothetical particle that transmits gravity) does. Or they are very small and circular. By circular I mean that if you travel far enough in that dimension you get back to where you started - like in the Meteors! or Maelstrom games where if you fly off the right of the screen you come back on the left. In the case of these dimensions, the width of the screen is of an atomic scale, so you would never notice the process of moving across it and coming back to where you started.

There are theories with other universes that are separated from us because of the way space-time might split in quantum mechanics (ala quantum leap and parallel universes) but that is a different use of the word 'dimension'.

torstan
06-26-2008, 01:49 PM
@ toff: nprb

@ Karro: Now that there is a top plan for at Cthulhu game... Hmmm, sounds like a fun start to an adventure.

@RPMiller: Forgot to mention, I looked it up. The expected data output is around 15 petabytes a year. That will be written to tape on site and simultaneously sent out to two or three other storage facilities around the world to avoid problems from data corruption, or say a fire. Each of those will be accessible from the Grid.

Karro
06-26-2008, 01:53 PM
@ toff: nprb

@ Karro: Now that there is a top plan for at Cthulhu game... Hmmm, sounds like a fun start to an adventure.


It came to me all at once upon reading your first post... I'd have posted it sooner but was distracted by work... :(

Is "NPRB" secret mad-scientist code? ;)

NeonKnight
06-26-2008, 01:53 PM
@Neonknight - There are many theories with extra dimensions, all of which differ on their nature. Every one of them has a good reason why we haven't seen them yet. These generally fall into one of two categories - either atoms can't move in them, but more exotic matter such as gravitons (a hypothetical particle that transmits gravity) does. Or they are very small and circular. By circular I mean that if you travel far enough in that dimension you get back to where you started - like in the Meteors! or Maelstrom games where if you fly off the right of the screen you come back on the left. In the case of these dimensions, the width of the screen is of an atomic scale, so you would never notice the process of moving across it and coming back to where you started.

There are theories with other universes that are separated from us because of the way space-time might split in quantum mechanics (ala quantum leap and parallel universes) but that is a different use of the word 'dimension'.

Wow! I can be a theoritcal Physicist by publishing a third theory of why we don't see other dimensions:

Here it is:

NeonKnight's Big Theory on the Reason we don;t see Dimensions beyond the 4 Known

They don't exist.**




Thank You!

**Just being cheeky/ I couldn't resist ;)

torstan
06-26-2008, 02:04 PM
@Neon - actually if they find them I'll be ****ed, I work on theories in the standard 4 :) When they prove they don't, I'll split the winnings with you...

@Karro: Yes.

jfrazierjr
06-26-2008, 02:08 PM
@ Karro: Now that there is a top plan for at Cthulhu game... Hmmm, sounds like a fun start to an adventure.


See.. what you do here is get some players who know nothing about whats going on with your work... start the game... freak them out with some really off the wall crazy crap(and I mean WAY crazy) in the game. Then tell then that the project you are working on is doing the same thing and try to convince them that the world "really" won't end like it did in the game.

Heh.. that's where RPMillers suggestino about animated gifs and the whole "fog" doing the show/hide tokens for a fraction of a second while moving closer to the players would be just freaking awesome in Maptool!

Joe

Arcana
06-26-2008, 03:03 PM
I had to do it...sorry...

May I now present to you the site of CERN LHC...August 2012.

jfrazierjr
06-26-2008, 03:50 PM
I had to do it...sorry...

May I now present to you the site of CERN LHC...August 2012.


heh.... you should have thrown in some of the world monuments being sucked toward the event horizon.....

RPMiller
06-26-2008, 03:59 PM
Heh.. that's where RPMillers suggestino about animated gifs and the whole "fog" doing the show/hide tokens for a fraction of a second while moving closer to the players would be just freaking awesome in Maptool!

Joe
Where/when did I post that idea? I have so many ideas that I often forget that I post them. LOL

töff
06-26-2008, 04:05 PM
CERN LHC...August 2012.lulz!!!!!!

jfrazierjr
06-26-2008, 04:13 PM
Where/when did I post that idea? I have so many ideas that I often forget that I post them. LOL


Somewhere over on RPTools when talking animated gifs. I found it cause I searched and asked a question about that feature in Maptools and thought your post was a good idea. Your example was something like a partially translucent fog overlay stamp and have the GM turn the bad guy tokens on and off between moving them closer to the players tokens. Kind of like a freaky strobe light horror movie effect.

RPMiller
06-26-2008, 04:15 PM
Ah, I vaguely remember that. Thanks!

Karro
06-26-2008, 04:46 PM
See.. what you do here is get some players who know nothing about whats going on with your work... start the game... freak them out with some really off the wall crazy crap(and I mean WAY crazy) in the game. Then tell then that the project you are working on is doing the same thing and try to convince them that the world "really" won't end like it did in the game.

Heh.. that's where RPMillers suggestino about animated gifs and the whole "fog" doing the show/hide tokens for a fraction of a second while moving closer to the players would be just freaking awesome in Maptool!

Joe

See, now that's just mean ;)


I had to do it...sorry...

May I now present to you the site of CERN LHC...August 2012.

I work in a cube farm, at least for today... This pic was incompatible with that fact. I almost broke the code of silence...

NeonKnight
06-26-2008, 04:51 PM
Am I the only one who keeps reading the title as on HARDon colliders, or am the only sicko here?:?:

Midgardsormr
06-26-2008, 06:09 PM
(hadrons are composite particles - of which protons and neutrons are two examples. Always be careful when typing hadron not to get the d and r mixed by accident. Easy typo, completely different machine....)

Evidently not.

I have something of the opposite problem. Imagine my chagrin when I clicked on a link to what I thought was going to be an enormous hadron.




Okay, that didn't really happen.

jfrazierjr
06-26-2008, 06:26 PM
The LHC - Large Hadron Collider
(hadrons are composite particles - of which protons and neutrons are two examples. Always be careful when typing hadron not to get the d and r mixed by accident. Easy typo, completely different machine....)



Am I the only one who keeps reading the title as on HARDon colliders, or am the only sicko here?:?:


Which is why Torstan explicitly warns you to be careful...:P

RPMiller
06-26-2008, 07:16 PM
Am I the only one who keeps reading the title as on HARDon colliders, or am the only sicko here?:?:
Looks like you're the only one. >:) ;)

Arcana
06-26-2008, 09:41 PM
I'm sporting quite a large Hadron right now...oh yeah!!!


Seriously though...Torstan, this thread was VERY enlightening, and I honor your work and look forward to the future through what you guys learn.

Ascension
06-27-2008, 01:59 AM
A year ago I would not have had the foggiest idea about this whole thread, but thanks to the Science Channel I can actually follow this. God love a couch potato...would that be dark matter wasting dark energy?

torstan
06-27-2008, 04:39 AM
Happy to have such an interested audience. If there are any interesting developments I'll add them on to the end of this thread. Equally if people have questions I'm more than happy to pull together some answers. It'll be an interesting couple of years in this field.

jfrazierjr
06-27-2008, 09:15 AM
Happy to have such an interested audience. If there are any interesting developments I'll add them on to the end of this thread. Equally if people have questions I'm more than happy to pull together some answers. It'll be an interesting couple of years in this field.

Hehe.... yea, be sure to post here if the world blows up so I will know about it....:D I would hate to walk out my door one morning and there not be anything out there.

Joe

RPMiller
06-27-2008, 11:16 AM
Oh, I have a question. Most Grids allow anyone to connect so that their computer can be used for processing data. Does this project allow for that as well, and if so is there a link that we can go to to join the Grid?

torstan
06-27-2008, 12:01 PM
Currently it is not a public Grid so unfortunately you can't link up to it from outside. I don't (and probably won't) have access to the Grid either as it - in its initial form - is almost entirely devoted to the experimentalists on the experiments for their data analysis. This will start soon after the LHC turns on, but the large data rates aren't expected until 2009 at the earliest.

They do have a sort of mini distributed tool which is LHC@home which, like SETI@home runs a programme on your home computer as a screensaver. That's not really Grid computing, as it can run happily for hours and then sends back results when its done rather than being assigned tasks in real time as part of one larger calculation being done across a network of machines.

This side of stuff really isn't my area, but I'm enjoying flicking through the info on the CERN website about it and giving you my understanding of the information I can drag out.

I don't know - I draw a piddly map and someone reps me. I prove* that the universe isn't going to be destroyed in a couple of months and everyone just passes on regardless. Priorities people? :)

*well, yes 'prove' is a little strong, but 'point people to a proof' is a little long winded.

jfrazierjr
06-27-2008, 12:11 PM
I don't know - I draw a piddly map and someone reps me. I prove* that the universe isn't going to be destroyed in a couple of months and everyone just passes on regardless. Priorities people? :)

*well, yes 'prove' is a little strong, but 'point people to a proof' is a little long winded.


I am still not convinced. What day did you say they are they going to turn it on? I want to make sure I have all my affairs in order just in case... of course, if we will all be obliterated, I don't really guess theres that much to do to prepare as there will be no after(assuming we are not shunted to some strange new dimension, in which case, I think I should probably make sure I have some food, a gun, and a few big knives just in case)


Joe

Redrobes
06-27-2008, 12:52 PM
...to prepare as there will be no after(assuming we are not shunted to some strange new dimension, in which case, I think I should probably make sure I have some food, a gun, and a few big knives just in case)Ok you do that. Me, well i'll make sure I am stood near to a bus load of cheerleaders. :P

Karro
06-27-2008, 03:55 PM
I don't know - I draw a piddly map and someone reps me. I prove* that the universe isn't going to be destroyed in a couple of months and everyone just passes on regardless. Priorities people? :)
[/SIZE]

Ah, but you've only offered evidence that you* won't destroy the universe in a couple months. It's everyone else that I'm worried about ;)

Besides, what if you change your mind?

*And ostensibly your colleagues.

RPMiller
06-27-2008, 05:04 PM
Yea, what happens if a bad man sets off a bomb at the moment the collision occurs and releases the black hole and infuses it with enough power to grow in magnitude and it in turn absorbs the energy of the the collider itself and while still growing begins to suck in the very planet we call home? We are all doomed!

This message brought to you by the letter B and the number 6.

torstan
06-27-2008, 05:09 PM
:) Yes we are, but only when the sun explodes in a few million(?) years. And no, that one isn't my fault either.

I heard that one physicist who was being interviewed about this said that it was far more statistically likely that a pink dragon would pop out of nothing and devour the earth than that the LHC would destroy it. To which the interviewer responded 'but it could happen?'. You can't win.

Ascension
06-27-2008, 05:46 PM
~5 billion...gives me plenty of time to finagle my way into getting Scarlett's cell phone number too.

Redrobes
06-28-2008, 08:43 AM
A serious question for Torstan... I know break the habit etc...

If in due course they do find the Higgs Boson and get a handle on gravity and maybe even further flung know the recipe to make gravitons or gravity waves or whatever, would that mean that we could have anti-gravity, gravity propulsion and levitation devices ?

Also, given that there are companies about like, I think they called, American Anti gravity which are alleged to do military work do you think that this sort of stuff already exists ? or do you think that there are similar systems using another method - they go on about Hutchinson effect or charged particle thrusters, lifters etc.

I.e. do you have any inkling that some people know a lot more about the stuff thats about to happen with the LHC than is public.

I'll take my tin foil hat off now.

torstan
06-28-2008, 09:31 AM
Having done a quick search on Hutchinson, it seems the only physics myth he doesn't claim to have created is cold fusion. As far as I can tell, he has admitted himself to being unable to replicate any of his effects after 1991 - which seems a bit bizarre given that they would be worth a fortune if they were true. He should know the physics behind it, and if he could replicate even a small example under test conditions then he would quickly become one of the richest men in the world. So no, as he is selling 'video evidence' for $100 a throw rather than drinking cocktails in the carribean, I don't think there is much to those stories.

However, the claims to have worked with the military are likely to be true. Military research budgets (as far as I understand it) do have room for blue skies research and something wildly unlikely but potentially of enormous use can still be a good investment for them. If someone claims to be able to do something remarkable, like create anti-gravity, then I believe that would be something that would be researched. I believe that such a project was looked into in the UK as well. I am unaware of any positive results from this stuff, but then I am as outside that circle of research as anyone else and so can't really say. What I can say is that there is no physical effect that I know of that can produce anti-gravity.

Now to the second part of your question. If we understand gravity at the LHC, will we be able to do something useful with it, like create anti-gravity. First off, a few qualifiers. The Higgs boson is the physical manifestation of the Higgs field, a field that gives particles mass. How that mass is then affected by gravity is a separate question. This separate question deals with gravitons, and the unification of quantum mechanics with relativity - through string theory, M-theory, loop quantum gravity or some other speculative theory. We will not break that problem at the LHC unfortunately. We may get some further hints how to proceed, but we won't get the answer.

However, we believe that gravitons exist. All forces have a particle that carry the force. Electromagnetism has the photon, the weak nuclear force has the W and Z bosons, the strong nuclear force has the gluon. All these have been experimentally proven. The graviton has not. f we were to be able to study a graviton then we would get some insight into the theory of gravity at the quantum scale which would be truly amazing. The unification of relativity and quantum mechanics is the holy grail of particle physics and one that Einstein died trying to achieve.

So that's all great, but how does it apply to anti-gravity. Well, the problem is that gravity is an attractive force. There are no negative gravitational fielsds around. This is unlike electromagnetism in which you get positive and negative forces. Just try to push two like sign magnets together and you'll see. We currently have no structure that gives a negative gravitational force. You can also think of it this way. Gravity comes from the warping of space and time (yes, I know, but stay with me). Space-time can be thought of as a rubber sheet (really, the maths is surprisingly close). Drop a hevy weight on a rubber sheet and you get a dip. Now if you place a marble on that sheet, it rolls towards it. The problem is that we only know how to make depressions in the rubber sheet, we can't pull it up. If we could figure out that then we'd have a way of creating anti-gravity.

There is one light at the end of this tunnel (and in factone that might show up in the LHC tunnel). That's the existence of dark energy. Now I mentioned dark matter - an exotic matter that doesn't interact with light but makes up 5 times more of the universe than atoms and molecules - but dark energy is even more mysterious. Basically the universe is expanding and it keeps getting faster. Now the only force acting on the scale of galaxies and above is gravity and it's only attractive. So if gravity is the only game in town then everything should be getting closer together, or at least be slowing down as it expands. This is not the case. And the amount of energy needed to maintain this behaviour is huge. This repulsive force has been named dark enegy, and no-one really knows what it is. It may be some form of anti-gravity, but it could be hundreds of other things as well. Given this is a huge gap in our knowledge, we expect a major revolution in physics when it is understood. And revolutions in physics come with useful, or at least interesting, spin offs.

The first effect of any great discoveries will be new terms and ideas popping up in science fiction. Some of them will be wildly off, but others may be possible. Given some time and clever experimental physicists and engineers, we'll get new gadgets and tools from this stuff that we can't possibly predict now. However, it is a good bet that a revolution in our understanding of gravity will have an impact on everyday technologies. I just don't think we'll see that revolution at the LHC.

So back to the question. I don't think there's any top secret research being done at the LHC. I'm certain that there's no hidden understanding of what's going to be found at the LHC. To know what it was going to find, you'd have to have built one already - and it is far too large and expensive for any one country, or small group of countries, to build on its own - let alone a company or military research unit. Also, if it could be done on a smaller scale, we'd know about it. Governments don't spend this much money unless they know it really can't be done any other way. Finally, CERN is an entirely non-military institution. No military budget is funding the LHC, and all the research is public. It's one of the only areas of science where you can read any item of research without paying for a subscription. All research is out there and available to anyone. Just go to here uk.arxiv.org, click on the experimental high energy physics link and browse until your heart's content. It's nice to work in such an open field - and the reason why I think there are no great secret plans.

Oh, my papers are here (http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=find+a+roberts%2C+jonathan+peter&FORMAT=WWW&SEQUENCE=) if anyone is truly bored!

RPMiller
06-28-2008, 12:33 PM
So the universe's expansion isn't the same as say air pumped into a container expands to fill the container?

torstan
06-28-2008, 12:41 PM
Nope. The reason air spreads out to fill a container is that there is air pressure. Now that is caused by the air molecules bouncing off each other. Galaxies and stars don't have that interaction to force them apart.

Now even in space the air molecules would keep expanding. That's because the molecules would be given an impetus when they were close together and bouncing off each other. They all keep on going in a straight line from the las point of interaction - so away from the place where they were close to the rest of the air. However they keep going at the same speed, or in a perfect vacuum they would slow down minutely due to the gravitational force from the other air molecules dragging them back.

The universe on the other hand does not seem to be expanding outward steadily at a constant rate. The rate of expansion is higher than can be accounted for by gravity and the initial impetus of the big bang. There needs to be some force pushing it outwards. Again, cosmology isn't quite my area, so that's a rough sketch of how I understand it to be, but might be a bit off.

RPMiller
06-28-2008, 12:51 PM
That's very interesting. That is the first time I heard about the expansion actually speeding up. I can definitely see why there would be a strong belief in something pushing outwards.

torstan
06-28-2008, 01:03 PM
Yep, the evidence definitely points to the universes expansion speeding up. There's some debate about the evidence because measuring the expansion rate of the universe right now is tricky, measuring its expansion rate millions of years ago is downright hard - and requires assumptions about stars - for example that a supernova we see today has certain key features that are identical to one that went off millions of years ago. However all the evidence, particularly that from the WMAP satellite, supports theories in which there is a pressure accelerating the expansion of the universe.

delgondahntelius
06-29-2008, 07:11 AM
humpf... I always thought the universe was static... its always been here.. it always will be... weird... this is all news to me...!!

Drazi
07-08-2008, 01:49 AM
measuring its expansion rate millions of years ago is downright hard - and requires assumptions about stars - for example that a supernova we see today has certain key features that are identical to one that went off millions of years ago.

Wouldn't most all things that we are able to observe in space today (supernova, galaxies, etc..) actually have happened millions of years ago since that is how long it takes for light to reach Earth? So, how is it that we're guessing here?

NeonKnight
07-08-2008, 05:29 AM
Wouldn't most all things that we are able to observe in space today (supernova, galaxies, etc..) actually have happened millions of years ago since that is how long it takes for light to reach Earth? So, how is it that we're guessing here?

I think it is the case of, Is a Super Nova we are seeing today (Date + 1 million years), equal to a super nova that would have been observed say 65 Million years ago (date + 65 Million, +1 million).

torstan
07-08-2008, 07:23 AM
Drazi, you are dead right. Things we see in the sky now did indeed happen many thousands or millions of years ago. The key is that a supernova we see that occurs 100,000 light years away occurred 100,000 years ago (the time it took for the light to reach us - light covers 1 light year per year). Another supernova that we see which is 1 million light years away must have occurred 1 million years ago. In this way, as we look at fainter and fainter supernovae, we are looking into the past of the universe. By studying their traits over increasing distance, we are able to measure the history of the universe. The problem is that this assumes that a supernova that occurred 1 million, or 10 million years ago has the same traits and structure as one that occurred 100,000 years ago. There's good reason to believe this to be the case, but its still a source of error that is being actively addressed.

Supernova have been observed as far away as 10 billion light years, so they act as very useful reference points when scanning the distant universe.

Drazi
07-08-2008, 01:42 PM
So, I was watching Nova Science Now on PBS and they had a special on Dark Matter. They mentioned in it that it is likely that a mass of dark matter in space could act like a lens and magnify the space beyond it. Is it possible to compensate for the added distortion when calculating things like rate of universe expansion and distance between galaxies?

torstan
07-08-2008, 01:53 PM
Absolutely. The lensing effect is well understood and is actually one of the ways of looking for dark matter. The reason for this is that a lens distorts as well as magnifying. Here's a galaxy acting as a lens on the light from a galaxy behind it:

http://blog.occamsmachete.com/files/gravitational-lensing.jpg

You can see that there are a number of long curving images in the picture, around a central bright galaxy. Now they are normal galaxies that are behind the bright galaxy. The light is bent around it, and the lensing effect distorts the image. Incidentally, as it is the mass of the galaxy that is distorting the light, you can use this effect to weigh the galaxy that is acting as a lens. Once again you come up short if you only consider the visible matter, and have to assume that there's a lot of dark matter too.

The point of all this is that if dark matter is acting as a lens, it doesn't just magnify an object, it also distorts the image of it. As long as we're really careful about checking for distortion, it's possible to precisely measure when an object is being lensed, and by how much. This allows astrophysicists to accurately place lensed objects, no matter what it is that is causing the lensing.

The science of gravitational lensing is now very precise and can be used to measure not just the mass of a lensing object, but also the precise distribution of mass throughout the object. It's a very useful tool.

Drazi
07-08-2008, 04:09 PM
Is it very likely for us to be able to study Dark Matter here on Earth without being able to create it ourselves?

And also, do we know if the presence of Dark Matter effects the way light behaves? I saw a special on the Science Channel about the Big Bang that mentioned that if the Universe was as old as today's scientific models claim than we shouldn't be able to see as much light as we do (I'm butchering the theory here so apologies for that). So they supposedly have a problem where the only solution was to change the speed of light from being a constant to being variable over time. Now they theorized that perhaps an outside force was acting upon the light just after the Big Bang that made it move faster than it traditionally should. So, the question is could the large concentration of Dark Matter/Energy at the time of the Big Bang affect the Speed of Light?

torstan
07-08-2008, 05:35 PM
Your last question first - there are a couple of fairly odd theories that incorporate a variable speed of light. You definitely don't need it, but I believe that some things fall out a little more neatly if you have it. Unfortunately my knowledge of those theories is pretty much non-existent. One of the main proponents of the theory is a guy called Joao Magueijo who's based in either Cambridge or Imperial at the moment - I forget which. If you are interested in this, google his name and VSL. Just don't believe everything that you read. It made a big splash a few years ago and then pretty much disappeared. I wouldn't put a lot of money on it.

Models of dark matter/energy generally don't affect the speed of light, just the way it moves. However the early universe is a weird place and there's a lot still to be understood about it that is still up in the air.

We do know that dark matter affects the way that light travels. One thing dark matter must have is mass. That's because it needs to have a gravitational pull to explain the rotation of galaxies that we observe, as well as the behaviour of clusters of galaxies. Now we also know that anything that gravitates also bends light. This was shown in the early 20th century when it was observed at an eclipse that astronomers could see stars that were behind the sun. The sun had bent the light from those stars around it so that they could be observed on earth. This was a key prediction of relativity over Newtonian gravity and was seen as one a proof of Einstein's relativity.

If dark matter has a mass - which it must - then it has to bend light as well whenever there is a lot of it in one place. This can be observed in so called dark galaxies. These are galaxies in which almost all of the luminous matter has been stripped away by collisions or some catastrophic event, but has left the dark matter galactic halo behind. This object is dark, but has an enormous gravitational pull. It shows up when you look at the bending of light.

Incidentally, the behaviour of light in a gravitational field is the reason balck holes are called that. The gravitational pull of a blakc hole is so strong that light cannot escape. Near the event horizon of a black hole, light is bent so strongly that it will curve in a perfect circle around the blak hole and never escape.

Right, finally we get to your first question. Is it very likely we can study dark matter here on earth if we can't produce it? Well there are two answers to that. Firstly, we might produce it on earth when the LHC turns on, so in that sense yes - hopefully we'll be able to create dark matter and study it directly. If we aren't able to then we can still study it in two ways. We can't create stars on earth, but we can get a really good idea of how they work by studying their existence in the universe around us. We look at the light they throw out and the effect of their presence on the objects around them and work back to a detailed understanding of what they do. We can do the same with dark matter. We already know what it does and doesn't do - it does have mass and a gravitational pull, it is electrically neutral and doesn't interact through the strong nuclear force. It is massively abundant and it is stable on lifetimes similar to those of the universe. So yes, we can study it without producing it. We'd get a better idea of what it was if we could produce it, but we're doing pretty well so far. Finally, even if we can't produce it, we can still find it - because it is already here. It keeps the galaxy together and is like a diffuse gas throughout the whole galaxy. If our theories of dark matter are correct then roughly 1 billion particles of dark matter are passing through each person's body every second. It hardly interacts at all, and when it does, we'd never notice it. So we build detectors that would notice such an interaction. In mines in Asia, the States and Europe there are detectors in operation and yet more being constructed in deep mines behind layers of shielding trying to find elusive interactions of the dark matter that permeates the universe around us. They will be able to test the theories of dark matter independently from the collider at CERN. If we find signals of dark matter in both places then we will have two separate windows on one of the great mysteries of the universe - and both sets of experiments should be reporting important data in the next few years.

Drazi
07-08-2008, 10:24 PM
Thanks for that response. As you might have guessed already I'm a bit of an armchair enthusiast when it comes to theoretical physics. I find the logic behind new theory to be very exciting. I've always equated theoretical physics to philosophy, in a way it seems to satisfy the same part of me that demands a logical system for things to work in. At a time I considered theoretical physics as a possible career choice, but I find the math involved with it to be tediously boring, I'm much more fond of the ideas and how they relate to on another. Anywho, thanks for the great info, I'll be posting again if I come up with more questions.

Looking forward to hearing about the collider in action.

-Drazi

torstan
07-09-2008, 03:39 AM
Well, you're preaching to the converted on that one. I did a joint honours in physics and philosophy. We did the maths in the physics course and read the original papers of Einstein, Bohr, Newton et al in philosophy. There is a lot of interesting philosophy going on in physics at the moment, especially while we wait for the new data.

I'm more than happy to keep answering questions - and will keep the guild updated on the collider as long as there is an interest :)

RPMiller
07-10-2008, 03:17 PM
Incidentally, the behaviour of light in a gravitational field is the reason balck holes are called that. The gravitational pull of a blakc hole is so strong that light cannot escape. Near the event horizon of a black hole, light is bent so strongly that it will curve in a perfect circle around the blak hole and never escape.
WARNING: Thread derailment imminent...

Just curious if these were intentional misspellings because of this:
http://cityhallblog.dallasnews.com/archives/2008/07/dallas-county-meeting-turns-ra.html

Yea, it is really ridiculous and I would suggest not reading the comments that follow it. I was just curious since they are all different.

Torq
07-10-2008, 03:30 PM
Well, you're preaching to the converted on that one. I did a joint honours in physics and philosophy. We did the maths in the physics course and read the original papers of Einstein, Bohr, Newton et al in philosophy. There is a lot of interesting philosophy going on in physics at the moment, especially while we wait for the new data.



One of the other boards that I visit a bit has a guy that has the following in his sig:

"Observer-dependent physics undermines the gods' decision 3000 years ago to ban cats from straddling the borders of the netherworld. We won't have it!". I laugh every time I see it.

Torq

torstan
07-10-2008, 03:35 PM
Oh dear :)

White holes are hypothesised to exist - they would be the opposite of a black hole - spewing out and almost endless stream of light and matter. They are hypothesised as the 'other end' of a black hole. But there again we head out of what I know and into the dark depths of wikipedia.

@Torq: That's an excellent sig. That should bait pretty much everyone on the science/religion divide.

Turgenev
07-15-2008, 12:27 AM
Just wanted to say this has been a great thread. I'm an armchair science nut. I might not understand it all but I love reading up on the stuff (especially astrophysics, astronomy, paleontology, archaeology, and biology).

When I hear about White Holes, I always think of the Red Dwarf TV show where Lister shoots pool with planets to close a White Hole. :lol:

torstan
07-15-2008, 11:34 AM
Absolutely, red dwarf was a stroke of genius.

I have to say that I've greatly enjoyed writing the posts in this thread (did the length of the posts give it away :) ?) and I'm glad that people are enjoying the read.

helium3
07-15-2008, 09:52 PM
Interesting.

I didn't know that failing to produce/find the Higgs Boson would result in disproving the entire Standard Model.

What are the competing theories that would then move up to replace it, if that happens? Or would theoretical physicists just stand around looking confused for a while?

Also, there's a pretty decent hard sci-fi book called "Einstein's Bridge" by John Cramer. It's about a mist-like event that occurs at the (never built in our timeline) SSC in Texas.

Oh, and I think the physics shop here at the UW in Seattle built some of the components of one of the detector modules. I've actually seen what they look like on the inside. Lot's and lot's of tubes. Not sure if the tubes were for coolant or "detector fluid."

torstan
07-16-2008, 05:35 AM
Failing to produce a Higgs boson will disprove the Standard Model. That doesn't mean it's not useful. The major elements of the structure will be part of any future theory. Think of it this way. We know Newton's theory of gravity is fundamentally wrong. It claims that gravity is a force that acts instantaneously at a distance. So if the sun vanished now, the earth would immediately stop going in a circle and start going in a straight line. Now that's not the case. From relativity we know that gravity is communicated by the shape of space and time, and that changes to that shape propagate at the speed of light. Therefore if the sun vanishes in an instant, the earth will keep going in a circle for around 8 minutes, until the effects reach us. However that doesn't mean that all the results of Newton's theory of gravity are null and void. We can still use it for most calculations about the movements of planets, the course of satellites and space missions with complete faith. However the vision of reality that underlies those equations is wrong. In the case of the Standard Model, if we don't find a Higgs boson then the structure that the Standard Model is based on is wrong. However, the equations that describe it do an excellent job of describing reality in all the situations we have investigated so far - and they will continue to be a good description for calculational purposes, whether we find a Higgs or not. It's just that if the Higgs ain't there, then we know the basic principles are wrong.

There are a few theories that would predict no Higgs boson. There's three reasons we might not see a Higgs boson, and each have theories associated with them.

1. The Higgs boson interacts very weakly to normal matter and could thus avoid detection. So it's there, and possibly even produced, but we don't see it.
2. The Higgs boson is very heavy, so it is outside the reach of this accelerator.
3. There is no Higgs boson at all.

Now 1 is very tightly constrained already. This is because a Higgs boson must couple to matter to give it a mass. So there is only so far you can go in making such a particle 'invisible' before it just stops doing its job. The only models I know of with such an invisible Higgs also have heavier Higgs bosons to help finish the job. An example of a model with a light invisible Higgs is the Next to Minimal Supersymmetric Standard Model (NMSSM). Yes, we are very bad at making up names. It's a failing.

In the case of 2 this is also pretty constrained. Now the standard model can't have a heavy Higgs. This is because the Higgs boson is tightly linked to the W and Z bosons, that have been found already. Now the Z boson has a mass of 91.14 (in units of giga-electron volts or GeV - it's a convenient unit of mass, because if we weigh things in grams the numbers are so small they get very cumbersome very fast). Now for a first calculation of the Higgs mass in the Standard Model you find that it must have a mass of equal to or less that the Z mass. However experiment tells you it can't be lighter than 114GeV. So you see the problem. A more detailed calculation in the Standard Model allows you to get up to about 135GeV before you run out of options. Now the LHC will run at an energy of 14TeV (=14000GeV) so we should definitely be able to produce a Higgs if it weighs less than 135GeV. So a heavy Higgs (outside the reach of the LHC) is well beyond what could be done in the Standard Model. Furthermore, because of the nature of the W and Z bosons, a heavy Higgs is always going to be very problematic as, by its nature, it must be directly involved with the W and Z bosons. If it is separated from them in mass by a lot, then this connection is very hard to maintain. To achieve this you need to alter the nature of the W and Z bosons from the form they take in the Standard Model.

You also need to do this if there is no Higgs boson at all - option 3.

As the Higgs boson is intimately related to the W and Z boson, the lack of a Higgs boson at the LHC will have clear implications for our understanding of those particles (that we can produce, and in large numbers). Models that have no Higgs, or a heavy Higgs, generally fall into the category of composite Higgs models, or extra-dimensional models. One clear problem is that if you take the Standard Model as is, and take out the Higgs, funny things start to happen. One such funny thing is that if you collide two W bosons off each other, then at high energy the chance of getting two W bosons out of the collision is greater than 1. Now that is definitely not allowed. The inclusion of the Higgs boson sorts this out.

So you can measure the odds of getting two Ws out of such a collision over a range of energies in your experiment and see whether the result agrees with the Standard Model or deviates from it. If it deviates, and you've found no Higgs boson, then you know you've found evidence of non-standard model physics. This would be an obvious place to look if we don't find a Higgs boson. This could tell us that the W and Z bosons are not fundamental particles, but that they are made up of smaller components - like an atomic nucleus is not solid but rather a collection of protons and neutrons. It could also tell us that W and Z bosons can move in extra dimensions of space that we haven't been able to access before. This can result in alterations to their collision behaviour which avoids the embarrassing problem of getting more out than you put in that I mentioned above.

So there are a few avenues to consider if we don't find a Higgs boson, and some obvious areas to study that should break if the Higgs boson isn't where we expect it to be. However, the expectation is that we'll probably find a number of different Higgs bosons as well as a slew of other stuff.

As for whether the scientists will be scratching their heads? Well, yes. It's not the expected result - and it will disprove a lot more than just the Standard Model if we don't find a Higgs - most of the extensions have one or more Higgs bosons in them already. However it will only be a few weeks before people start coming up with weird and wonderful solutions that fit the data and can themselves be tested. Hence the progress of science :)

Hmmmm, that got a bit long and technical. Sorry about that. Hope it wasn't too heavy. If you want me to clarify any of it, please say so.

Yes, the SSC (Superconducting Super Collider) was never built - though they did dig the tunnel. It was supposed to do what the LHC is doing now. They screwed up the budgeting for it and congress threw it out. It's now one of the most expensive mushroom farms ever built. I'll have to look out that sci-fi book you mention. Sounds like an interesting read.

NeonKnight
07-16-2008, 06:01 AM
I theorize that the reason we see no Higgs boson is because they exist outside the 4 dimensions we know. :P

Redrobes
07-16-2008, 08:18 AM
Heres a set of wooly questions. So the engineers finish the building tweaking and tuning and hand the keys to the big red button to the physicists. Whats the order of tests that they would perform - i.e. is looking for Higgs the first test and is that going to be done with the two W boson probability test thing. Its like building the Hubble and asking so what do you point it at first ?

Also, I am not clear about how you try to generate a Higgs Boson. Is the idea that you accelerate matter in the ring and then crash it into each other ? What matter do you accelerate ? Does it have to be a stream of protons or something like that or does the accelerator just gain more energy in massless 'particles' and then these new particles just take some of this energy and create themselves. If not then whats special about the matter used that is thought to create the Higgs. Doesn't all the matter go around the ring at the same speed or is it switched into a stationary 'block' of something and thats where all the action takes place.

And...(as if that wasn't enough)... why doesn't the system create more lighter particles instead of one heavy one - is that just down to probability and you get a slew of everything.

torstan
07-16-2008, 08:52 AM
That is indeed quite a series of questions. I'll try to get through them all, but not necessarily in the order they were asked:

1. Is the idea that you accelerate matter in the ring and then crash it into each other?
Yes.


2. What matter do you accelerate?
Protons. This is because they are charged - necessary if you are going to accelerate things with an electric field. Also they are relatively heavy in the world of subatomic particles. This means they don't lose as much energy when spun round a ring. Electrons lose a lot, which is why they aren't used any more.


3. Doesn't all the matter go around the ring at the same speed or is it switched into a stationary 'block' of something and that's where all the action takes place?
Half the protons go round the ring one way, half the other. They collide head on at two points on the ring. That's where the energy is produced, from the annihilating matter in the protons. It's this energy - that only gets created here - that allows for the production of new particles.

4. Does it have to be a stream of protons or something like that or does the accelerator just gain more energy in massless 'particles' and then these new particles just take some of this energy and create themselves?
It can be any type of particle that has mass - because massive particles must couple to the Higgs. It must also be charged - hence the proton. Actually the proton is a collection of quarks - which are the things that really collide. The quarks do couple to the Higgs and so can be used to create one.

5. Why doesn't the system create more lighter particles instead of one heavy one - is that just down to probability and you get a slew of everything.
It will create more light particles than heavy ones. Most of the interactions will spit out a massive array of Standard Model particles and experimentalists will have to hunt for the interesting new signals amongst that morass. That's really why we need the vast computing power of a world wide grid. We're hunting for one MB sized needle in a petabyte of haystack.

The exception is when you are precisely on the mass of the particle you want to produce. Then there are effects that kick in that greatly enhance the likelihood of getting that state over other states of different mass. But yes, fundamentally it's quantum mechanical, so it is always about probabilities.

6. What's the order of tests that they would perform?
Well sadly this isn't like the Hubble. This machine just does one thing. You turn it on at one energy and then watch what comes out. It will precisely measure every interaction for 10 years. If some of those interactions produce interesting stuff then we are in luck.

6b. So the question really is, when we get the first years data set, what's the first thing the experimentalists will look for in it?
The first thing to look for is the Standard Model. Not a Higgs, but all of the W and Z bosons, the quarks, electrons and so on. The Standard Model has never been studied at these energies before, so they need to understand that before they go any further. Then they will look for a heavy copy of the Z boson. This is predicted by a few theories and is really easy to spot. Then they'll go to work on the Higgs, as that is the most widely sought particle. They'll also look for weird and wonderful new signals such as dark matter.

If they find nothing, then they start looking at W-W scattering. The reason to wait is that this is a subtle effect - not the production of a new particle, but rather the modification of the scattering of two particles. Now rmember we're colliding protons, not Ws, at the LHC. That means the Ws are going to have to have been created from a proton-proton collision and then have been created in such a way that they collide with each other - and then we still have to be paying enough attention to have seen it. So it's a phenomenally tricky measurement to make - and probably won't be done unless we really need to figure out what's up with our broken models.

So the order is:
1. Find the Standard Model again
2. Look for easy signals - like a heavy Z (imaginatively titled the Z')
3. Look for the Higgs (well even experimentalists can't resist the lure of a Nobel Prize)
4. Look for clear signals of the big contenders for theories of physics - supersymmetry and extra dimensions. This will be a matter of looking for dark matter and fancy new particles
5. Look for the tricky signals - such as WW scattering. These tend not to involve the creation of new particles, but are instead a modification of existing processes.

Redrobes
07-16-2008, 09:18 AM
Thanks, thats really lit up some dark corners about all of this in my head. I studied electronics so I did bits of Maxwells and Schrodingers but there are only a handful of everyday electronic components that work at the quantum level so I never did any subatomic physics, not counting the electron of course. Its really interesting and moving very fast.

torstan
07-16-2008, 09:57 AM
Roughly the speed of light normally :)

Sorry, couldn't resist.

Ascension
07-21-2008, 01:02 AM
Don't know if any of you knew this or not, but this weekend there were 2 separate programs on the LHC on the Science Channel...one called "The 6 billion dollar experiment" and another called "The big bang machine". I watched em both cuz, well, that's what I do while I map, unless there's a Cardinals game on.

torstan
07-21-2008, 03:55 AM
Yep, there was a big article on the BBC as well talking about how the LHC was set to become the coldest place in the universe which isn't an unreasonable claim.

2 weeks to start up if nothing goes wrong.

Were the programs any good?

jfrazierjr
07-21-2008, 08:03 AM
Yep, there was a big article on the BBC as well talking about how the LHC was set to become the coldest place in the universe which isn't an unreasonable claim.

2 weeks to start up if nothing goes wrong.

Were the programs any good?

Hey, my birthday's in 3 weeks! Any chance for a short delay so I can get my birthday presents before the world implodes? ;)

On a side note, everything I see this thread pop up, I misread the word collider and replace it with the word colander and wonder why I am all of a sudden very hunger for spaghetti.

Joe

Arcana
07-23-2008, 04:50 PM
I just realized that torstan never commented on my rendering of the CERN site in 2012...I'm terribly offended (or maybe torstan is)

edit: I just lol'd at the tags

torstan
07-23-2008, 07:02 PM
I was wondering how long it would take for someone to notice. Unfortunately only the 'dark matter' one makes the tag clud search :)

Good alteration to the CERN site actually. Geneva is one city that could only be improved by the addition of a black hole. Just my opinion of course.

jfrazierjr
07-23-2008, 07:29 PM
I just realized that torstan never commented on my rendering of the CERN site in 2012...I'm terribly offended (or maybe torstan is)

edit: I just lol'd at the tags


I was wondering how long it would take for someone to notice. Unfortunately only the 'dark matter' one makes the tag clud search :)

Good alteration to the CERN site actually. Geneva is one city that could only be improved by the addition of a black hole. Just my opinion of course.


Heh.. you still should mock one up with some of the worlds monuments being sucked in....:)

yu gnomi
07-31-2008, 11:18 PM
I hadn't expected to find a thread about high energy physics at this sight, but it is a very pleasant surprise.

Regarding Dark Matter: From what I can gather (mostly from watching TV programs like "Nova") theorists speculate that dark matter is exotic, and not the same as matter we are familiar with.

What I don't understand is why dark matter couldn't be ordinary bits of matter like space dust, space rocks, etc?

Or even less tangible, but ever-present particles like neutrons and neutrinos?

Turgenev
08-01-2008, 02:03 AM
I'm not really a rap fan but the Large Hadron Rap has to be heard to be believed. 8)

http://www.youtube.com/watch?v=j50ZssEojtM

torstan
08-01-2008, 05:56 AM
We know that there is a certain amount of space dust in the universe - in fact there is a lot of it. Dust and gas make up the dominant source of 'normal' mass. However both dust and gas do interact with light. Hydrogen has a very specific spectrum at which it absorbs and re-emits light. That means we can 'see' it by looking for dips in a spectrum at the relevant frequency. The same actually goes for dust and rocks. Because dust absorbs light, we can see how much of it there is by noting how obscured light is from distant objects. Basically there's an important distinction here. 'Dark' in the context of dark matter means that it doesn't interact with light, not that it absorbs it. So gas and dust and rocks can't be the dark matter because they do interact with light.

Neutrons and neutrinos are another matter. Neutrons can't be dark matter for two reasons. Free neutrons are unstable, decaying after about 15 minutes into a proton, an electron and a neutrino. The proton will capture an electron and form hydrogen. So there's no chance of having neutron dark matter. Also, neutrons are strongly interacting. If there were 1 billion neutrons streaming through us, we'd notice. To an atom, an incoming neutron looks like a ten ton truck. Note that high energy neutrons are what split uranium nuclei to cause nuclear fission. They're pretty destructive.

Neutrinos are a different matter. They have mass (just), they are weakly interacting, they are electrically neutral and they are stable - so they cover all of the relevant criteria for dark matter, and indeed they were proposed as a solution as soon as it was discovered that they had mass. However those theories have been disproved. There are two reasons for this. Firstly, there simply aren't enough of them. They are weakly interacting, but not so weakly that we can't detect them. There are huge detectors in deep mines that have been studying neutrinos for years - one up in Sudbury, another in Japan and smaller ones around the world. They have pinned down a decent measurement of the number of neutrinos in the universe and it isn't even close to the number that would be required to make up the missing mass. Note that neutrinos are incredibly light - at least 10 billion times lighter than a neutron - so you would need a lot of them to make up all the missing mass. The second reason they can't be the dark matter is more subtle. Basically, neutrinos travel very fast - almost at the speed of light. s such they are known as 'hot' matter. This means that they don't really notice the effects of gravity.

To explain this I'm going to have to use a bit of an analogy. Gravity works a bit like a large shallow bowl. If you send a ballbearing around a shallow bowl it will roll in a spiral, dropping towards the center as it loses energy. If there were no friction, the ball-bearing would roll in a circle forever - like an object in orbit. The space around a massive object is curved, just as the bowl is and this causes objects to orbit the heavy object. Space is frictionless, so planets move in circles rather than spirals. Now consider the situation where you roll a small light ball bearing into the bowl at high speed - it just goes in one side of the bowl and out the other. It may well come out at a slightly different angle, but it won't stay in the bowl. This is the case with neutrinos. Because they are moving so fast, they don't get trapped in so called 'gravitational wells', even when the well is created by something as massive as a galaxy, or cluster of galaxies. They go in one side of the dip and come straight out the other side. This is a problem. We know from the way that galaxies rotate that the dark matter must be arranged in a cloud around each galaxy with the highest density at the center. This can only happen if the particle that makes up the dark matter can be trapped in a gravitational well. For this to happen, it must be a slow particle, or 'cold'.

So we now know that dark matter must be cold, as well as all the other properties that have been assigned to it. That rules out neutrinos.

torstan
08-01-2008, 05:57 AM
@turgenev: That's great! Thanks for the link.

RobA
08-01-2008, 08:10 AM
I'm not really a rap fan but the Large Hadron Rap has to be heard to be believed. 8)

http://www.youtube.com/watch?v=j50ZssEojtM

You beat me to it! (another boingboing reader?)

-Rob A>

yu gnomi
08-01-2008, 10:19 AM
Wow that was quick. Thank you Torsten for the thoroughness of your answer and the speed with which it was posted.

I figured that there had to be some reasoning as to why the normal everyday cases of matter were ruled out as being dark matter, but I've simply never seen it explained. Your responses all made sense to me.

I know that there are now theories that galaxies, including our own, circle around black holes. Could it be that dark matter is simply black holes (and maybe neutron stars, which I believe are similar) ?

I do realize that this would mean a lot of black holes and neutron stars.

Turgenev
08-01-2008, 11:09 AM
You beat me to it! (another boingboing reader?)

LOL! Guilty as charged. ;) When I saw that vid I instantly thought of this thread.

torstan
08-01-2008, 11:23 AM
Yes, our galaxy rotates around a supermassive black hole - and indeed we know how massive the black hole is. Neutron stars also exist, they are collapsed stars that are not massive enough to form a black hole. They consist only of neutrons (hence the name) and are as compact as the nucleus of an atom, but are macroscopic (big) objects. They are therefore the densest material in the universe and pretty exotic.

So you are right that both of these types of objects are large heavy objects that don't emit light. They are also very localised and so wouldn't show up through their obstruction of light (you'd have to be able to resolve something about a kilometer wide as far away as alpha centauri to see the shadow of a neutron star). So they get around the dust evidence too.

As I understand it there's a few reasons why it can't be black holes or neutron stars. Firstly, and I think least convincingly, is that we can see black holes and neutron stars to some extent. Black holes pull in matter and collect a disk of host gas and dust around them. As this gas falls into the black hole, it's going pretty fast and there are interactions with the rest of the dust that's falling in. This gives off radiation and can be seen. So though we cannot see the black hole itself, we can see the accretion disk of matter that it gathers. Okay, so you could have a black hole without a disk for some reason, or a lot of small black holes without visible disks or so on, but it would be had to justify where all of them come from. Equally, neutron stars spin and there are effects on the objects around them that allow us to get a fair estimate of how many there are.

The reason I don't like that answer is because it relies on complete faith in our pretty indirect methods of detection of these objects. However I am not an astrophysicist so I can't tell you what kind of errors you'd expect on the measurement (estimate?) of the amount of mass that is bound up in black holes and neutron stars.

The other reasons that I find a little more convincing are firstly that we know that the mass of dark matter must be distributed throughout the galaxy, and that this distribution should be relatively smooth. In contrast, a load of black holes would be lumpy. You can measure the movements of stars and use that to constrain the distribution of the mass that they are being affected by. I have been to a couple of talks that have claimed that we can now show that large concentrations of matter are now ruled out by such tests, but again, I'm not an expert on those studies. Also, they tend to rely on large numerical simulations of galaxies to prove their results and people aren't certain about the accuracy of those yet. We probably need more computer power to answer that one conclusively.

However the best reason I know of is that dark matter has to have existed in the early universe. By studying the last light from the big bang we see that there must have been a lot of matter that did not interact strongly with the plasma. Now all the matter we know of would interact strongly, so we need something else. The same matter is needed to amplify small fluctuations in the early universe and turn them into galaxies and stars. Now neutron stars and black holes are both the results of dying stars so our evidence for dark matter precedes the time at which we expect black holes and neutron stars to appear on the scene.

That's the reasons I can think of off the top of my head. Obviously each has ways out and we definitely need to obtain a better estimate of the amount of matter in neutron stars and black holes in the universe, but the weight of evidence seems to say that they aren't the matter we're looking for,

yu gnomi
08-01-2008, 01:55 PM
I've taken some college physics, but dark matter, dark energy and a lot of other cutting edge theoretical stuff, hardly ever got a mention in the courses I took. Every resource I've found via search engine on these topics is either too dumbed down to be useful, or too advanced for me to possibly understand. Your replies are pleasantly neither. Thank you.

While a lot of aspects of the standard model are completely beyond my ken, I do know that finding the various particles responsible for the various forces is ultimately essential. I'm optimistic that they will succeed, although I don't believe that the standard model will get thrown away overnight if they don't. I'm always keen on learning about the scientific cutting edge.

Oh yeah, in case you didn't read my introductory post, thanks for recommending this site to me.

jfrazierjr
08-01-2008, 03:21 PM
Ok, so it's now August.... exactly which day does the world end? I seem to recall you saying it would be before my birthday on the 13th, so I need to get all my partying planned out before I die....

torstan
08-02-2008, 03:43 AM
I believe that around the 13th is still current. Nobody's saying any more than that yet. I'll let everyone know if I find out any more.

RPMiller
08-02-2008, 11:48 AM
I have a question. What is it going to be powered with, and how loud is it going to be when it fires up?

torstan
08-05-2008, 06:56 AM
It gets powered off the standard electricity grid. They buy in a large quantity of electricity and that is drawn in from French power stations.

I don't think it will make much of a noise when it starts up - though you'd have to hope that it would make kind of whoooom-thrum-thrum-thrum noise. Sadly the noise of a hadron collider was never covered in my courses :)

I guess not a lot of noise though as there are no moving parts. It's a matter of large magnets and electrical currents - the same as a TV screen just on a much larger scale. So there's no obvious source for noise. As for the collisions themselves, they are very small and a very long way away from anyone who might be able to hear them. So I guess it's a matter of - does a colliding proton beam make a noise if there's no-one there to hear it?

Other news - it looks like the beam people have done their job and the ring is pretty much ready to take the beam. Now it is a matter of getting the two detectors (ATLAS and CMS) finished so that they can close the caverns and turn it on. This is good news and means there should be a beam in the ring in August, but it's looking like first collisions will be pushed back a little. There are conflicting reports from different people and no official news yet, so it's still a little unclear. I'll post more when I find out more.

Oh, and Yu-gnomi. Thanks for the comments. That's precisely the balance I've been trying to strike. I'm glad I'm succeeding to some extent!

Midgardsormr
08-06-2008, 01:40 PM
I guess not a lot of noise though as there are no moving parts. It's a matter of large magnets and electrical currents - the same as a TV screen just on a much larger scale. So there's no obvious source for noise.

So I take it you're one of those lucky people who can't hear the flyback transformer in a TV.

Lessee, these particles are travelling near the speed of light, yes? So that's 299,792 km / s. The thing is 27 km in circumference, so that gives a frequency of about 11.1 kHz, which is about where the letter 'S' lives, if I recall my equalizer cheat sheet correctly.

So if it were exposed, it would sound like an enormous snake, but frequencies that high are easily absorbed by the earth, so I doubt anyone will be able to hear it.

torstan
08-07-2008, 11:21 AM
Well the particles themselves are travelling in a vacuum so they shouldn't create any noise. However the electromagnetic currents that are used to accelerate them in the radio frequecy cavities are likely to cause stresses on the machine that will create noise. However any noise is lost energy, as well as repetitive stress, so I'm guessing that they have minimised it as much as they can. Interesting note about the frequency though. I love the fact that the LHC should sound like 's'.

torstan
08-14-2008, 02:09 PM
Update, the first particles should go round the ring on the 10th of September. That's the official date released by CERN. No collisions that day I expect but hopefully closely following it. So it looks like I might get my wedding in before we definitely don't end the world.

RPMiller
08-14-2008, 02:27 PM
Sweet! Going out with a bang is always a good idea. ;)

torstan
09-01-2008, 10:14 AM
:)

Sorry for relative silence recently - in the middle of 2 international moves and a wedding, will be posting more regularly during October when I have internet in new home in NY!

New study out relatively recently on LHC safety: http://arxiv.org/abs/0806.3414.

My favourite quote from the abstract:
"Any microscopic black holes produced at the LHC are expected to decay by Hawking radiation before they reach the detector walls." (my emphasis)

So that's okay then :)

Arcana
09-01-2008, 10:43 AM
So...are you moving to NY because you have a new job not working on the LHC or are you moving to NY because you're fleeing the imminent danger of a black hole sucking in all of EU?

torstan
09-01-2008, 11:26 AM
New job, still working with the on dark matter at the LHC. You lot funded it too :) I'll be at NYU for one year for sure and hopefully a couple more. I guess I'll be doing some teaching at NYU as well as research. Should be fun! Though knowing my luck NY will stand up to its Hollywood reputation of being ground zero for most major disasters and the New York collider - RHIC (Relativistic heavy Ion Collider) - will produce a black hole from colliding gold atoms....

delgondahntelius
09-01-2008, 11:20 PM
congrats on the move and job and all that.... travel safe and hurry up with the maps :D you know we all can't wait for your next big map :D

RPMiller
09-02-2008, 02:00 PM
Looks like all systems are a go: http://news.zdnet.com/2424-9595_22-217914.html

delgondahntelius
09-02-2008, 02:19 PM
Looks like all systems are a go: http://news.zdnet.com/2424-9595_22-217914.html

"I got a baaad feeling about this..."

First star wars quote has been noted @ 1:20 pm Sep 2, 08

Valarian
09-02-2008, 03:02 PM
Any Black Holes or rips in the space-time continuum yet?

torstan
09-02-2008, 03:22 PM
Not yet, but then they just* sent a small bunch of protons a hop skip and a jump around the ring - 3km of a possible 27km. No collisions yet. The test was done to see whether the little ring (the SPS) could throw a bunch of protons into the bigger ring without the bigger ring fumbling the catch. Now think how much difficulty the American relay teams had doing this stuff last week (yes, the Brits screwed it up too, but I can't say I expected much more...) and this one has to be done with sub-microsecond precision. That was definitely a non-trivial manoeuvre and they deserve a lot of credit for managing it first time.

It'll be interesting to track the large number of 'End of the World!' stories as a function of how close we get to the LHC start next week (note that there will be no collisions for a while, and they will be low energy when they start).

Here's my first contribution:
http://www.dailymail.co.uk/sciencetech/article-1051070/Landmark-experiment-unlock-secrets-Big-Bang-cause-end-world-say-scientists-court-bid-halt-it.html

If you get any, post them here.

*For a given value of 'just'

RPMiller
09-02-2008, 03:59 PM
Here's my first contribution:
http://www.dailymail.co.uk/sciencetech/article-1051070/Landmark-experiment-unlock-secrets-Big-Bang-cause-end-world-say-scientists-court-bid-halt-it.html

So do whack jobs like that get stripped of their scientist badge or anything? I mean I have to think that everything you've pointed out thus far is in the scientific norm and can't understand how anyone calling themselves a scientist wouldn't know this stuff. Maybe I'm missing something?

Redrobes
09-02-2008, 04:16 PM
From daily mail article...

Within four years, one of these 'celestial vacuums' could have swollen to such a size that it is capable of sucking the Earth inside-out.

Four years ??? That's a pretty slow exponential growth then. So if you have a while, then if you discover one of these holes in the middle of your machine infinitesimally small but growing, can you just hold it there and wait for the Hawking radiation to evaporate it ? Would you need to be able to control its position ? Does that imply a need for a graviton/gravity wave generator to move it or do you move bits of mass about to position it.

RPMiller
09-02-2008, 04:20 PM
I just realized something. If a black hole forms inside the collider, wouldn't that stop all future experiments since the black hole would then suck in any future particles that go near it? I think that would be a good indicator that there might be a black hole forming.

Valarian
09-02-2008, 05:26 PM
Just have to quote Babylon 5 here ....

No boom today... boom tomorrow. There's always a boom tomorrow.

jfrazierjr
09-02-2008, 09:09 PM
Not yet, but then they just* sent a small bunch of protons a hop skip and a jump around the ring - 3km of a possible 27km. No collisions yet. The test was done to see whether the little ring (the SPS) could throw a bunch of protons into the bigger ring without the bigger ring fumbling the catch. Now think how much difficulty the American relay teams had doing this stuff last week (yes, the Brits screwed it up too, but I can't say I expected much more...) and this one has to be done with sub-microsecond precision. That was definitely a non-trivial manoeuvre and they deserve a lot of credit for managing it first time.

It'll be interesting to track the large number of 'End of the World!' stories as a function of how close we get to the LHC start next week (note that there will be no collisions for a while, and they will be low energy when they start).

Here's my first contribution:
http://www.dailymail.co.uk/sciencetech/article-1051070/Landmark-experiment-unlock-secrets-Big-Bang-cause-end-world-say-scientists-court-bid-halt-it.html

If you get any, post them here.

*For a given value of 'just'



Hmmm... 8/8/8 sounds like a triple digit date that would be a great day for the world to end.

torstan
09-03-2008, 04:15 AM
Unfortunately you can discredit people all you like but they can still call themselves scientists as long as they can produce evidence of a PhD, unlike doctors who can have their status stripped by the medical council (I believe). So nutters who really think that we'll destroy the world can take it to a paper and get equal say to the scientists and because everyone loves an underdog almost as much as they love a disaster story it gets printed.

Redrobes: You are right, black holes form slowly due to the capture of matter. They also lose mass through Hawking radiation. For a large one, the accretion of matter is much faster than the decay but for a small one the decay is much faster than the accretion and a microscopic black hole should never become a large black hole. For something other than this to happen, the laws of physics would have to be very different from what we think they are. As the CERN report pointed out, if you change the laws of physics you usually see an effect of it somewhere else first - in this case through cosmic rays hitting earth, or any other nearby large object. Essentially, these collisions are happening on all objects in space and none of the nearby celestial bodies have been swallowed by a celestial void or black hole yet so we are fine.

RPMiller: If a black hole formed and did not dissipate then it would be affected by gravity, so it would gravitate to the center of the earth (like any massive object). It would not be very heavy, so it would take a bit of time to do this. It would cause damage at the atomic scale (though very little in reality) as it travelled. Once at the center of the earth it would slowly accumulate matter (hundreds of years is a number I've heard thrown about but I haven't done the calculation myself) until it became large enough to be an issue. Again, if it were to happen here, it would already have happened all over the universe, and especially in our solar system. We don't see objects being eaten from the inside by black holes, so it is safe. But the short answer to your question is that the black hole only sucks matter in by gravitational force, and it only has the mass of the objects that created it. Now two hydrogen nuclei are pretty light so the gravitational force is fantastically small. Therefore the experiment would be able to occur around it without feeling any effect from the gravity of the black hole. Only when it got large would it start to affect the experiment, and by that time it will have moved outside the area of the detector.

Valarian
09-03-2008, 05:04 AM
For something other than this to happen, the laws of physics would have to be very different from what we think they are.
It'd be a hell of a time to go "Oops" though. I can just see red-faced scientists trying to explain why Switzerland is sinking. :D


Therefore the experiment would be able to occur around it without feeling any effect from the gravity of the black hole. Only when it got large would it start to affect the experiment, and by that time it will have moved outside the area of the detector.
:D So what you're saying is that, even if a black hole is created, we won't know about it until it eats the Earth because it's travelled outside the detector range. Comforting ;)

Turgenev
09-05-2008, 08:30 AM
This just blows my mind...

Scientists get death threats over Large Hadron Collider (http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2008/09/05/scilhc105.xml)

There are a few other interesting links in that article as well.

Valarian
09-05-2008, 08:39 AM
There's a perverse part of me that really wants all the scientists to be wrong and they have to go "Oops". Then again, it'd mean that the doomsayers are right and I'd hate that.

Morshwan
09-05-2008, 10:42 AM
I am living not so far from the Hadron collider. When they will launch the first test, I will try to post here to tell you how dark is the black hole ;-)

Arcana
09-05-2008, 12:11 PM
I had to do it...again...this one is animated :arrow:

RPMiller
09-05-2008, 12:14 PM
I am living not so far from the Hadron collider. When they will launch the first test, I will try to post here to tell you how dark is the black hole ;-)
Something tells me that the Internet access may be an issue. ;) LOL

RPMiller
09-05-2008, 12:15 PM
I had to do it...again...this one is animated :arrow:
You stopped too soon. Isn't the Earth supposed to get turned inside out? ;)

torstan
09-06-2008, 01:09 PM
@Arcana: That's brilliant! I'll definitely be passing that round the office....

torstan
09-06-2008, 01:13 PM
@Turgenev: Much as I dislike the telegraph, that's actually a very reasonable article. Thanks for the link.

Redrobes
09-07-2008, 08:58 AM
Beeb has a whole section of their web site devoted to it now !

http://news.bbc.co.uk/1/hi/sci/tech/7543089.stm

Hope you caught El Regs slightly more irreverent take on the whole thing :)

http://www.theregister.co.uk/2008/09/05/lhc_to_leave_fabric_of_spacetime_continuum_unrippe d/

torstan
09-09-2008, 05:27 AM
Very good. Yes I noticed the BBC is having a big bang day. It's nice to see a physics experiment generating so much interest - it's just a shame we won't get big results for 18 months!

Redrobes
09-09-2008, 05:48 AM
Yes, its great. Maybe all physics experiments should have the capability to swallow the earth so that the media get interested ! All the astro radio telescopes funding got the chop in the UK and the ISS is going to be stranded by the US as from 2010 from a lack of shuttles unless there is a rethink about NASA funding. Perhaps they are not dangerous enough to open administration and government purse strings.

And what you doin' in Scotland now. I thought you were over the pond now you jet setter :)

torstan
09-09-2008, 06:15 AM
I've had a bit of an international month of it. Poland to the UK at the start of the month - along with a separate removal of a full flat's worth of furniture, a month in the UK including wedding next weekend and then off to NY at the end of the month. I'm currently down in Southampton teaching students how to do dark matter calculations.

The BBC does seem to have latched on to the destroying the world aspect - which is fair enough as it is a great way to capture people's imaginations. The down side is that people phone up in abject fear and ask us not to do it - this happened to my old supervisor yesterday. It will be great for the funding bodies to see an experiment they funded getting so much attention, particularly as particle physics is usually way too dry to get much attention. We're always jealous of the astrophysicists as they get all the pretty pictures and everyone therefore thinks that space is cool (which it is).

The LHC was exempt from the cuts this year because the UK is legally tied into funding it. The question will come when the next collider is planned. If the LHC doesn't find anything exciting then it will be extremely hard to convince the funding bodies to cough up - again you'd have to feel that that was fair enough. The problem comes if we find nothing at all - because that would be a huge result - as it would disprove a theory that has stood for decades. However convincing governments that not finding something was really exciting is a pretty hard sell!

And just a short clarification - a few of the radio telescopes that were going to be dropped got refunded again as it would have cost the UK too much to pull out. However the STFC funding debacle was a bit of a nightmare. Hope that all sorts itself out.

jfrazierjr
09-09-2008, 10:42 AM
So, whats the point of this experiment? If won't blow up (or implode as the case may be), whats the point? I mean, is this expected to find us a new power source for cheap efficient energy (I kind doubt it given how much it costs), or solve world peace (well, if the world ended, it would achieve that objective), cure hunger, or give all the people of the world free health care?

From a armchair conspiracy theorist who pretty much made D's in physics in high school, I just don't get the point. Oh, and don't you dare say "just to see if we could":P.

I mean, are there any real expected improvements to society that are expected within a few years of the project gathering its data (assuming the world does not implode) or do we just not know what might be dreamed up until it is dreamed?

torstan
09-09-2008, 12:16 PM
Funnily enough this question is getting asked quite a lot at the moment. Everyone is saying that it costs a lot. Yes, it cost £3 billion which is objectively an awful lot of money. This money is split between contributions from all the countries involved and has been spent over more than 10 years of research, development and construction. It's still a lot of money - but remember that the money is sourced from a lot of countries so the orders of magnitude are a little different from normal - and still a tiny fraction of what the US spent on the invasion and occupation of Iraq (over a mush shorter time period).

Right, now the finance is out of the way let's get on to the point of the whole endeavour. First let's note that the LHC should be compared to experiments such as the Hubble space telescope. It is a scientific instrument designed to progress the knowledge of a branch of physics. If we'd gone out to design a new power source we'd be working on fusion power and creating a fusion power station - which is actually happening and costing a similar amount of money. In that case the cost is in the design, and should allow cheaper power stations to be built in countries around the world later that generate power from water and lithium.

The LHC will advance our knowledge of theoretical particle physics. This is useful to humanity because it will provide useful technologies further down the line. Electromagnetism was a purely theoretical construct in the same field that now gives us everything to do with electricity and electronics. Relativity was a dry theory about the speed of light which now gives us lasers and theories of radioactivity and nuclear power (and yes, the bombs too - that's one reason CERN bans cross-over technology proposals with the military). We don't know what theories will arise out of the collider, because if we knew the next theory, we wouldn't have to build the collider. I can assure you though that as soon as we know what the new theory is, there will be lot of very clever and ambitious people trying their damndest to come up with industrial applications.

In the shorter term, the experiment has a load of useful spin-offs - the previous collider gave us the protocol that runs the web. This one should mark a sea-change in the scale of distributed computing with the creation of the largest ever distributed computing network - the Grid. As CERN is a non-profit based organisation, these inventions are allowed owed into the world for free. Equally, the work at CERN has led to developments in climate modelling, cloud formation, medical imaging, cancer treatment and the safe disposal of radioactive waste through nuclear transmutation. These developments can be used by the countries that fund CERN and provide an economic and social benefit. Any time a new experiment is proposed at CERN it has to show that the technologies developed will be of use in wider society.

So we have built it to search for new theories. That's the goal. We expect the end result to benefit society. We know that the technology developed on the way there is already benefiting society.

Importantly, there are very few international collaborations of this scale in the world and very few endeavours that require this level of technological innovation. If there were no LHC, many of these technologies would never be developed.

jfrazierjr
09-09-2008, 12:45 PM
And if all else fails, Switzerland will have the worlds largest indoor dog walking park.....umm that cost 3 billion pounds....I hope the dogs really appreciate the expense....;)

Micco
09-09-2008, 05:50 PM
I think the HLC is exactly the right thing to be doing as a joint world project. The benefits will be very similar to the race to the moon...lots of secondary and tertiary technologies that will drive the next economies and improve the human condition. If we are very lucky we'll figure out some real fundamental knowledge that will change everything (like figure out how to tap into ZPE!)

I think a manned mission to Mars needs to be on the short list of the next great joint ventures. We need to get some breeding pairs off the planet before it is devoured by black holes! ;)

Seriously, I'm somewhat if a lay-fan of Stoichiometric Electro-Dynamics. Any chance we'll learn more about that huge energy constant sticking on the end of all those complex unifying theories? (Understanding that, being a particle physicist, you probably are not a fan of SED...)

torstan
09-09-2008, 06:20 PM
Well Zero Point Energy and enormous wealths of free energy are generally considered to be myths, but it's well outside my field so I can't really take them on from much of a point of knowledge. I do know that you don't get any serious seminars about them, so I think they can probably be kept in the cupboard with the perpetual motion machines. However that is a sociological rather than scientifically based view. I'm afraid for a fuller answer you'd need to ask someone else (or I have to brush up on a few of the other areas of physics).

jfrazierjr
09-09-2008, 06:34 PM
I think the HLC is exactly the right thing to be doing as a joint world project. The benefits will be very similar to the race to the moon...lots of secondary and tertiary technologies that will drive the next economies and improve the human condition. If we are very lucky we'll figure out some real fundamental knowledge that will change everything (like figure out how to tap into ZPE!)

I think a manned mission to Mars needs to be on the short list of the next great joint ventures. We need to get some breeding pairs off the planet before it is devoured by black holes! ;)

Seriously, I'm somewhat if a lay-fan of Stoichiometric Electro-Dynamics. Any chance we'll learn more about that huge energy constant sticking on the end of all those complex unifying theories? (Understanding that, being a particle physicist, you probably are not a fan of SED...)


Well Zero Point Energy and enormous wealths of free energy are generally considered to be myths, but it's well outside my field so I can't really take them on from much of a point of knowledge. I do know that you don't get any serious seminars about them, so I think they can probably be kept in the cupboard with the perpetual motion machines. However that is a sociological rather than scientifically based view. I'm afraid for a fuller answer you'd need to ask someone else (or I have to brush up on a few of the other areas of physics).

OH OH OH.... I want my ZPM. I wanna power a flying city or an Antarctic super weapon. Gimme, gimme, gimme.....

Micco
09-09-2008, 07:26 PM
Interesting. I'll have to go dig up the references to it, but about two or three years ago I did quite a bit of reading on some research being done by the Physics Department at Cal State. They were investigating Stochastic Electrodynamics as a unifying theory. It appears from the Wikipedia Article (http://en.wikipedia.org/wiki/Stochastic_electrodynamics) that "classical" physicists are still quite opposed to the notion. Not like that hasn't happened before.


All four papers are today recognized as tremendous achievements—and hence 1905 is known as Einstein's "Wonderful Year". At the time, however, they were not noticed by most physicists as being important, and many of those who did notice them rejected them outright. Some of this work—such as the theory of light quanta—remained controversial for years.[26][27]

But, of course, I'm not seriously comparing Haisch to Einstein (but you never really know, do you?) Ironically, SED is fundamentally based on Plank's arguments against quantum mechanics in his series of papers entitled The Theory of Heat Radiation.

I understand that the "Zero Point Field" is considered to be in the land of crackpots, but I found the SED theories to be very intriguing and possessing a certain elegance that Particle Physics is sorely lacking. Call me a simple engineer (you'd be right), but I just don't believe that the universe is as complicated as particle physics demands. While (as an engineer) I value empirical learning, I am left wholly unsatisfied with the results when the objective is ab initio understanding based on first principles. But that's just me. ;)

None-the-less, HLC will at least keep the particle physicists busy with the pretty lines...and maybe we'll discover that there really is "mana" available to power our spells after all! Just let me know when that HLC comes up with a good explanation of the Casimir effect! ;)

torstan
09-10-2008, 04:49 AM
Note its the LHC not the HLC.

I'll have to look into those now. Any references you have would be good and I'll see if I can give a more intelligent answer than 'it's not my field but it smells fishy'!

Other news - first beam has made it around the LHC. That was the stated goal for today. Now they will try to get the second beam in the opposite direction.

Valarian
09-10-2008, 05:10 AM
I think they can probably be kept in the cupboard with the perpetual motion machines.
You mean strapping buttered toast to the feet of a cat doesn't work?

torstan
09-10-2008, 05:36 AM
I have to say that was always my favourite one. Unfortunately as cats are quantum beasts (c.f. schroedinger) they never stay where you put them. The cat/toast machine is fundamentally unstable.

Micco
09-10-2008, 07:37 AM
but it smells fishy'!

It is definitely fishy!! But that doesn't mean it's not possible. And I found it strangely compelling in a science fiction type of way. So my interest is likely more "hope" than anything else. I'm also a skeptic in the true sense of the word...I am skeptical of both the quacks and of those who dismiss them out-of-hand.

The elegant explanation of the Casimir Effect (http://en.wikipedia.org/wiki/Casimir_effect) is what has me wondering, somewhere deep in the recesses of my mind, if maybe these guys are on to something.

NeonKnight
09-10-2008, 07:54 AM
DON'T LOOK AT THE CAT!!!!!!!!!!!!!

You'll KILL it!!!!!!!!!!!

Steel General
09-10-2008, 10:39 AM
Cats, I hate cats...I'm extremely allergic to the durn little furry beasts. :(

RPMiller
09-10-2008, 11:26 AM
So it appears that all your work is for nothing Torstan. At least that is what Hawking says, and if he says it than you know it must be true. :roll:

http://www.breitbart.com/article.php?id=080909150154.yzfml9cn&show_article=1

Valarian
09-10-2008, 11:42 AM
It could be Prof. Hawking's habit of backing something both ways.
i.e. If the LHC finds something, he loses $100 but gets the joy of CERN having discovered something. If CERN fails to find anything, at least he gets $100.

He did something like this for his black hole theory (a complete set of the Encyclopaedia Britannica vs. a year subscription to Playboy IIRC).

torstan
09-10-2008, 06:11 PM
Well, not quite. He says they won't find the Higgs boson, but goes on to say this:



While questioning the likelihood of finding Higgs Bosons, Hawking said the experiment could discover superpartners, particles that would be "supersymmetric partners" to particles already known about.

"Their existence would be a key confirmation of string theory, and they could make up the mysterious dark matter that holds galaxies together," he told the BBC.


I work on supersymmetric dark matter. Nuff said.

I think they should find the Higgs, because almost any theory suggests you should see it. To hedge my bets though I have a paper on a Higgsless model, because frankly we don't know and I don't want to be out of a job if they don't find it!

torstan
09-10-2008, 06:22 PM
Favourite link of the day:

http://hasthelargehadroncolliderdestroyedtheworldyet.com/

RPMiller
09-10-2008, 06:26 PM
Favourite link of the day:

http://hasthelargehadroncolliderdestroyedtheworldyet.com/

I saw that over on the RPTools forum thread and just about fell out of my chair laughing. That is awesome!!

Steel General
09-10-2008, 07:13 PM
Favourite link of the day:

http://hasthelargehadroncolliderdestroyedtheworldyet.com/


Gotta like it, short and to the point! :D

Airith
09-10-2008, 07:52 PM
http://hasthelhcdestroyedtheearth.com/

Heh I thought they were the same. Anyways, I'm kinda on the fence about how it went today. I mean awesome we're still here, but I was hoping it would all end, I have it in my mind it would be hilarious. Maybe I'm crazy :D

Ascension
09-11-2008, 12:05 AM
Now that's my kind of website! Short and to the point, nothing misleading, no spin, easy to navigate, excellent :)

RPMiller
09-11-2008, 11:44 AM
Check out the HTML source for the site. Specifically look at the comment tags. ;)

Oh, and if you don't find it. He created an RSS Feed for the page. :lol:

Turgenev
09-11-2008, 04:17 PM
Check out the HTML source for the site. Specifically look at the comment tags. ;)

Oh, and if you don't find it. He created an RSS Feed for the page. :lol:

Oh man, that's just hilarious! I love it.

RPMiller
09-12-2008, 11:22 AM
Um... it looks like we may have a problem. Webcam at the collider:

http://www.cyriak.co.uk/lhc/lhc-webcams.html

Here is a great "rap tutorial" on the collider. Actually quite educational.

http://www.youtube.com/watch?v=j50ZssEojtM

Big_Mac over the RPTools forums posted these links. Thanks go to him. :)

Turgenev
09-12-2008, 02:44 PM
Um... it looks like we may have a problem. Webcam at the collider:

http://www.cyriak.co.uk/lhc/lhc-webcams.html

That was quite funny. I've seen that link floating around for a while now but this was the first time i actually looked at it.


Here is a great "rap tutorial" on the collider. Actually quite educational.

http://www.youtube.com/watch?v=j50ZssEojtM


I agree about the rap tutorial. It is a great link so that is why I posted it back on page 9 (post 86) of this thread. :lol: To those who haven't seen this vid yet, it is worth checking it out. I even added it to my Facebook page. ;)

RPMiller
09-12-2008, 02:49 PM
I posted it back on page 9 (post 86) of this thread.

But I'm only on page 4. ;)

Redrobes
09-13-2008, 03:50 PM
Just in case the 6 billion doesn't discover the Higgs Boson then don't worry, you can now just buy one for $9.75 :)

http://www.particlezoo.net/individual_pages/shop_higgsboson.html

Midgardsormr
09-13-2008, 04:12 PM
Wow. It really is an enormous hadron.

RPMiller
09-13-2008, 04:21 PM
*snicker* :lol:

ravells
09-18-2008, 07:05 PM
Here is the webcam from CERN (http://www.cyriak.co.uk/lhc/lhc-webcams.html) so you can see the world implode! :)

RPMiller
09-19-2008, 12:31 PM
Here is the webcam from CERN (http://www.cyriak.co.uk/lhc/lhc-webcams.html) so you can see the world implode! :)

ROFL, apparently we like that one a lot. ;)


Um... it looks like we may have a problem. Webcam at the collider:

http://www.cyriak.co.uk/lhc/lhc-webcams.html

Here is a great "rap tutorial" on the collider. Actually quite educational.

http://www.youtube.com/watch?v=j50ZssEojtM

Big_Mac over the RPTools forums posted these links. Thanks go to him. :)

Drazi
09-25-2008, 02:05 AM
I thought, since it hasn't been mentioned yet in this thread, that I would plug a couple of things I enjoy.

First off: The Big Bang theory - A show about a bunch of physics nerds. Really funny stuff, definitely worth a watch.

http://www.youtube.com/watch?v=9eTUz61LNjo

And second: Dr. Who (or rather the Dr. Who spin-off- Torchwood) - Recently there was a BBC radio drama featuring Torchwood. The cast has been called to CERN to solve a mystery at the LHC. Yes, it's a shameless plug for the LHC, but it's worth the listen.

http://www.bbc.co.uk/radio4/bigbang/torchwood.shtml

torstan
09-25-2008, 05:39 AM
Yep, the launch went really well. Unfortunately things haven't been so rosy since then. They had a massive helium leak that meant that the magnets warmed up by around 100 degrees and stopped being superconducting. That lead to a small explosion in the tunnel. Nothing too serious thankfully, but it means it needs to be slowly warmed up (takes a few weeks), checked and fixed and then cooled back down again. They won't get it cold again until the scheduled winter shutdown so no more particles in the pipe until the spring restart at full energy. It shouldn't affect anything as spring was the scheduled start of the full energy beam anyway, but it is an unfortunate turn of events.

I almost missed it in the news as I was away getting married. Now that is done, all I have is the small issue of moving country before I am a regular on the boards again. Here's looking forward to a good October! (No one's got a spare flat in NYC they just happen to need to let do they? :) )

jfrazierjr
09-25-2008, 08:11 AM
I almost missed it in the news as I was away getting married. Now that is done, all I have is the small issue of moving country before I am a regular on the boards again. Here's looking forward to a good October! (No one's got a spare flat in NYC they just happen to need to let do they? :) )


Congratulations! Looking forward to you being stateside.

Ascension
09-25-2008, 06:19 PM
I saw a headline about this the other day and had to do some serious digging in order to retrieve it. Bit o humor that I thought was pretty funny.

http://www.bbspot.com/News/2008/09/squirrel-smasher.html

torstan
10-01-2008, 12:27 PM
Very good. More squirrels should be collided at high speeds.

I made it to the US! I'm now in my shiny new office at NYU and settling in nicely. All I need now is an apartment and I'll be golden. Hopefully that will be nailed by the end of the week.

RPMiller
10-01-2008, 12:40 PM
Welcome to the States! ;)

Hm... your location says you in the south of England. :?

torstan
10-01-2008, 02:54 PM
Fixed. Unfortunately changing the CG location was not high enough on my to do list :) Never again.

RPMiller
10-01-2008, 04:07 PM
Hm... but you could just be saying you are in NYC, but not actually there so as to throw off your pursuers. ;)

Drazi
10-16-2008, 04:12 PM
http://i47.photobucket.com/albums/f178/drazi421/n186300117_30144763_9258.jpg

Ascension
10-16-2008, 10:08 PM
That is awesome! I'm putting that pic on my work station...although I'm probably the only one who will understand it.

Turgenev
10-17-2008, 09:42 AM
That's hilarious, Drazi! :lol:

torstan
10-17-2008, 12:16 PM
Oh dear, and here was me trying to keep this thread clean...

:D

Drazi
10-17-2008, 03:22 PM
Pfft, it's still clean. If you don't need a translation to tell you why it's funny, than clearly you don't need to have it censored from you. :P

torstan
10-29-2008, 03:09 PM
Okay, a small update. Unusually for this field there have been some dramatic developments. Firstly, there is news on the LHC.

The bad news is that the LHC suffered an unfortunate incident in which a ton of liquid helium escaped after an electrical fault. In the technical report it mentioned some damage to 25 magnets (that's a lot, each full magnet using it the length of an articulated lorry) but CERN has assured everyone it has enough spare parts to repair them all. The safety systems worked, but the damage will take at least until the spring to repair. The LHC was scheduled to be off over winter anyway so this isn't too much of an issue. Unfortunately it means that the scheduled work for the winter - getting the LHC ready for its first full energy run - will have fewer people working on it. That means the LHC probably won't start at full energy, bt will instead (hopefully) make it to full energy some time in the summer of next year. So its a set back but not a catastrophic one.

At the same time there have been new developments in space! A satellite experiment called PAMELA has reported that it has found a lot more antimatter than we ever expected to be up there. They've also found that the anti-matter has a distinctive energy. One theory (and the leading one at the moment) is that dark matter is annihilating in the galaxy and producing electrons and their anti-particle positrons with lots of energy. Those then fly through the galaxy and some of them hit the satellite. If this is true then we have just seen the first experimental signal of dark matter annihilations and we have a lower limit on the dark matter mass. That has, unfortunately, ruled out a couple of my predictions, but has opened up some interesting possibilities. So its interesting times for dark matter.

Obviously happy to answer questions if anyone wants to know more.

RPMiller
10-29-2008, 03:32 PM
So I assume that means that the LHC still hasn't destroyed the world? ;)

Are there any suspicions of sabotage? We have seen a lot of crack pots and their worries, I'm wondering if they could have done something by working on the inside.

Can you explain more about the "dark matter annihilating"? I'm not sure if that is a typo or I'm just not following it. Does that mean that dark matter is "less strong" and more likely to be destroyed rather than destroy something else?

torstan
10-29-2008, 04:35 PM
Its not sabotage thankfully. There was a pressure control valve that was faulty. It slowly opened when it should have remained shut and let liquid helium out. They found another couple that had the same fault so its manufacturing rather than sabotage. They'll replace them over the winter as well as cleaning up the damage from the problem.

The dark matter can annihilate with itself. In particle physics we see that a particle and an anti-particle can annihilate. So if an electron and a positron (its antiparticle) hit each other then they annihilate to energy. Now we believe that whatever particle dark matter is made of has the bizarre property of being its own antiparticle. This means that if two particles of dark matter hit each other then they can annihilate to energy. This energy then produces two particles - in this case an electron and a positron.

Now when two particles annihilate, their mass turns into energy. The amount of energy is given by E=mc^2. Now c^2 is a large number so you get a lot of energy for your mass. When that energy is turned back into matter - ie when the electron and positron are produced - you use some of that energy to create the mass - again through E=mc^2 - and the rest is kinetic energy. So by measuring the kinetic energy of the produced particle, you can find out information on the mass of the particles that annihilated to produce them.

Now the issue here is that they've found positrons with energy that would require the annihilation of a particle with at least a hundred thousand times more mass than an electron, and about a hundred times the mass of a proton, and this gives us our first hint about the mass of dark matter. It means that the dark matter must be at least has heavy as an iron atom for example. Now an iron atom is a large object made of all sorts of substructure whereas we currently believe that the dark matter particles are fundamental objects - so that's pretty heavy.

The fact that dark matter can annihilate is nothing too remarkable. If it hits normal matter it won't disappear - it has to hit another dark matter particle. In the same way, if an electron hits a proton it won't disappear, it has to hit a positron.

RPMiller
10-29-2008, 05:45 PM
Science is cool... 8)

torstan
10-29-2008, 06:18 PM
Repped for making my day!

jfrazierjr
10-29-2008, 07:47 PM
Does it scare the hell out of anyone else that they went "opps, mechnical failure caused something we did not anticipate in a project dealing with hugh amounts of energy in an attempt to create/detect theoretical particles that we really don't understand".



You know it's a bad sign when the scientist says uh-oh, and and then runs from the room.

Ascension
10-29-2008, 07:59 PM
Doesn't bother me at all, it just gives me something new to map :)

RPMiller
10-29-2008, 10:36 PM
Doesn't bother me at all, it just gives me something new to map :)
Would that be post-apocalyptic Europe? :twisted:

Ascension
10-29-2008, 11:36 PM
I'll leave that for the Alternate Earth guys, I'm gonna jump into the black hole and map that sucker so no one gets lost when we all get whooshed in :)

jfrazierjr
10-29-2008, 11:49 PM
I'll leave that for the Alternate Earth guys, I'm gonna jump into the black hole and map that sucker so no one gets lost when we all get whooshed in :)


Actually, given that you have more mass than the computer or paper you are using to map with, I suspect you have those items ripped from your hands.... Of course, I have NO clue what the hell I am talking about, so I am sure Torstan (or someone else) will tell me just how bad I am mangling physics with this absurd statement.

torstan
10-30-2008, 10:02 AM
Well objects of different mass fall at the same speed - true of a black hole just as it is true here on earth. However close to a black hole the difference in gravity at your feet and your head (if you are falling in head first) is huge, so your body would be torn apart by the tidal forces as your head gets pulled in faster than your feet - well its almost Halloween, the thread deserves a little gore.

I have no worries about the fact that the LHC threw a mechanical fault. The thing that went wrong is an engineering problem. The physics that we are testing is a theoretical physics problem. The two aren't really related. One thing I can say for sure is that the LHC is unlikely to destroy the world until late 2009 at the earliest :) as that is the first time it is likely to hit full energy.

Edit: Woot - 2 pips!

Steel General
10-30-2008, 12:37 PM
Woot - 2 pips!

WooHoo!!!!!

Congrat's Torstan - we are having an epidemic of multiple rep pips lately.

Ascension
10-30-2008, 09:57 PM
Physics schmysics, I'm a mapaholic. Whenever I get a new game I get more enjoyment out of mapping out the whole thing than by playing it...been doing that since MUDs were all the cool thing.

CC_JAR
11-02-2008, 01:36 AM
At the same time there have been new developments in space! A satellite experiment called PAMELA has reported that it has found a lot more antimatter than we ever expected to be up there. They've also found that the anti-matter has a distinctive energy. One theory (and the leading one at the moment) is that dark matter is annihilating in the galaxy and producing electrons and their anti-particle positrons with lots of energy. Those then fly through the galaxy and some of them hit the satellite. If this is true then we have just seen the first experimental signal of dark matter annihilations and we have a lower limit on the dark matter mass. That has, unfortunately, ruled out a couple of my predictions, but has opened up some interesting possibilities. So its interesting times for dark matter.

Obviously happy to answer questions if anyone wants to know more.
Ha, that's interesting, before I had even read this part, I had planned on asking what correlation dark matter had with anti-matter, if any. still a valid question though.

Another question I had planned on asking kinda deals with the same thing you're talking about there.
people have already experimented with creating anti-matter right? yet as soon as it's created doesn't it sort of attach its self to matter and null?
so what if dark matter has some sort of this effect?

CC_JAR
11-02-2008, 01:38 AM
I had to do it...sorry...

May I now present to you the site of CERN LHC...August 2012.

And as for that pic..
they just had to divide by zero, didn't they?

torstan
11-18-2008, 01:52 PM
Sorry CC_JAR I read the second of your posts but not the first. Didn't mean to ignore this question.

Yes, anti-matter does annihilate when it hits normal matter - as long as they are of the same type. So an anti-electron (a positron) will annihilate when it hits and electron, but not when it hits a neutron (for example). The same is true of dark matter, you would expect a dark matter particle to annihilate when it hits another dark matter particle. However the dark matter is so widely spread out, and the particles are so effectively tiny, that the odds of a dark matter particle hitting another are close to zero. Hence there is a lot of dark matter left over from the early universe when it was created. As it is not of the correct form to annihilate with normal matter it is harmless to us.

As for 'normal' anti-matter - we have indeed been playing with that for a long time. You are right in saying that if it hits anything after it has been created then it tends to annihilate. That's because only stable antimatter (antimatter that won't decay on its own) is the positron, anti-proton and anti-neutron. Now those are precisely the anti-matter versions of normal matter - electrons, protons and neutrons. Thus if stable anti-matter hits an atom, there's always something there it can annihilate with. The way around this is to create antimatter and then not let it touch anything. To do this you use a strong magnetic field. This doesn't work with neutrons - they have no charge so don't get affected by magnetic fields - but works well with positrons and anti-protons. If you keep them in a vacuum and use a magnetic field to keep them away from the walls of your vacuum container then you can build up a store of them and hold them indefinitely.

This is what was used in LEP - the predecessor of the LHC. LEP stands for Large Electron Positron collider. So they were colliding antimatter and matter together. The Tevatron in the US - currently the highest energy collider in the world - collides protons and anti-protons. So we are definitely able to create and manipulate anti-matter on a regular basis.

torstan
11-18-2008, 01:53 PM
LHC Update

Bad news I'm afraid. The LHC isn't going to turn on again until June at the earliest. The repairs are estimated to cost £14 million and they haven't even finished the full analysis yet. Not the most illustrious start ever. Ah well.

RPMiller
11-18-2008, 02:19 PM
That's a bummer... Looks like they'll be putting off destroying the world for quite a while longer. ;)

Interestingly my son is currently studying periodic table in his 8th grade science class. Just helped him put together a Potassium atom last week. Apparently one of the other students mentioned the LHC and the teacher was apparently clueless regarding all the really "deep" stuff that you've been explaining. I told my son he should come here and read up on it. :) Unfortunately he isn't that excited about it... apparently he doesn't think it is relevant to his currently chosen profession of doctor.... Yea, not looking forward to that college tuition bill. ;)

RPMiller
11-18-2008, 02:23 PM
I forgot to ask my question... :( So what is it about the anti-matter that makes it get destroyed by matter? That has always been a big question of mine.

torstan
11-18-2008, 05:01 PM
Hmmm, it's all a bit quantum. The first time that you get the creation and annihilation of matter is in quantum field theory. In QFT you have to understand particles as the excitations of a field. The interaction of particles is then the interaction of modes of a field. Now you cannot have a continuous spectrum of excitations of the field - they are quantised. We identify these quanta as particles.

Right, now we've got fields with states that we interpret as particles. When those states interact we are interested in the interaction of fields. The details of this are seriously messy - but the quantising of fields throws up things called creation and annihilation operators in your maths that correspond in reality to the creation and annihilation of particles. When you construct consistent theories with this framework you find that some things must be conserved. These are called quantum numbers. Now an electron carries a few different quantum numbers - one of which is called lepton number. A positron carries the opposite quantum numbers. Therefore you can have a term in your equations in which an electron and a positron annihilate because their quantum number cancel out. Before the interaction you had a total lepton number of 0 (+1 for the electron, -1 for the positron) and after the annihilation you have a photon, and a lepton number of 0 (photons don't carry any lepton number).

Unfortunately that's about as far as I think I can go without actually writing equations. I know that it's a bit like saying 'because they do' (spot the sentence above that could be substituted for that :) ). If you've got any specific questions then ask away and I'll do what I can to answer them.

RPMiller
11-18-2008, 05:07 PM
So a photon is a light particle right? Is it a field that produces light... er something? I guess the related question would be what exactly is light?

torstan
11-18-2008, 05:25 PM
Light is an excitation of the electromagnetic field.

There's a useful distinction to bring in here. There are bosons and fermions in the world. These are two separate types of particle that are differentiated by something called spin. Spin is another of those quantum numbers. It's not that these things actually spin round, but rather that the maths of spin is similar to the maths of angular momentum. Anyway, a fermion has a spin of 1/2 (or more generally half integer) and a boson has a spin of 0 or 1 (or more generally integer values).

All very good, but what use is this? Well it turns out that bosons are force carriers whereas fermions make up the matter in a theory. So quarks and leptons (that include electrons) are fermions whereas photons - the particles of light - are bosons.

Forces appear in a theory when you impose something called gauge invariance. Now this is the equivalent of saying that if you do certain things you don't expect there to be any physical change. Say for example that you have a perfectly circular cake. You rotate it any amount and it's still observably identical to how it was before you rotated it. That's called rotational invariance. Now say you draw a line straight through the middle. It's now only rotationally invariant for rotations of 180 degrees, 360 degrees, 540 degrees and so on. You have broken the continuous symmetry down to a discrete one.

Right, this is going somewhere, trust me.

Now if you construct a theory in which there are only electrons an you require it to obey a symmetry - in this case the symmetry of quantum electro-dynamics - then you find that you can't. If you apply a transformation to your electrons you get an observable result. To make sure it obeys the symmetries you have to introduce a new particle that interacts with the electrons in a very specific way. The new particle must be a boson. You then find that this particle is massless and only interacts with charged objects. We call it the photon. It is the particle that carries all electromagnetic force.

Now it turns out that our eyes also interact with photons that have certain energies - so we can see them. Hence light is a subset of electromagnetic radiation. Hope that makes a bit of sense.

RPMiller
11-18-2008, 05:33 PM
Wow... it actually does... for the most part. So if photons are massless, how do they interact with a reflective surface and "bounce".

torstan
11-18-2008, 05:45 PM
The short answer is that they interact with the electrons that surround atoms - they get absorbed and then re-emitted. The direction they are re-emmitted in is (I believe) governed by the conservation of momentum. I'm not 100% on the details of optics and there's definitely a whole load of complicated physics that gets you from individual particles back up to large scale optics with diffraction, refraction and so on but the basic process is the interaction of photons with the electrons in the atoms.

RPMiller
11-18-2008, 06:05 PM
That seems simple enough to understand. Thanks for answering all the questions.

BTW, this all gives me ideas for possible superhero powers at some later date. ;)

torstan
11-18-2008, 06:55 PM
Not a problem at all. I'd be intrigued to hear about the ideas for powers!

RPMiller
11-18-2008, 06:59 PM
That's the cool thing about the Hero System, you build powers based on special effects... Quantum Man can destroy matter by firing his Quantum beam of anti-protons... that sort of thing.

In the system that would be simply built as Ranged Killing Attack, Armor Piercing, Penetrating. So not even armor would completely protect you unless it was Hardened x2. ;)

torstan
11-18-2008, 09:48 PM
That's quite neat. I may have to look at Hero when I get a chance to actually play some games again. Moving country seems to have eaten my free time, and trying to organise games over a 5 hour time difference is a bit of a killer.

If quantum is the defining feature of your person the best property would be something like blinking (to use an easy D&D analogy). Quantum behaviour is best embodied by the probabilistic behaviour of objects that only become deterministic when you look at them. So a quantum person would be in a number of places at once until someone looked at them - at which point they would be in a specific place. Anyway, enough physics for tonight.

RPMiller
11-18-2008, 10:00 PM
That can be done a number of ways. I would give him transdimensional movement, and teleportation. Probably desolidification to allow him to pass through objects would be an option as well.

Perhaps I'll consider running a MapTool session of Hero some time. ;)

Steel General
11-19-2008, 06:11 AM
Something like Dr. Manhattan from the Watchman story?

RPMiller
11-19-2008, 10:45 AM
Oh! Yes, I can see the similarity there for sure. Of course he was even more powerful than my suggestions, but yes good example.

torstan
11-19-2008, 04:55 PM
Just went to an interesting talk by a Cern physicist who has spent the last year working solely on issues of safety of the LHC. Unsurprisingly the conclusion was that there is no chance that the LHC could destroy the world. However he made an interesting point that I had not appreciated. I was wrong when I said that cosmic ray data rules out any chance that the LHC processes could destroy the earth. The reason is that when a cosmic ray hits the atmosphere, the results of that collision are moving very fast. Think of it this way, a car hits another car head on, the two stop. A car hits another car at rest and after the collision the two cars move in the direction the first was travelling in. Now a cosmic ray is an example of the first situation, whereas the LHC is an example of the second. The amount of energy in both cases is the same - so the 'damage' to the entities involved is the same, but the remains of the collision are moving at different speeds in the two cases.

So why do we care how fast the remains are moving? A slow black hole is the same as a fast one right? Well, not quite. Take the worst case scenario where all we know is wrong and we can create stable neutral black holes in particle collisions then a black hole created by a cosmic ray collision would be moving so fast that it would exceed the escape velocity of the earth and go tearing off into space. It would pass through the earth and have no effect. However a black hole created at the LHC would be moving slowly and would gravitate to the centre of the earth and start to grow.

Now we need to find out whether such a thing could be possible. Now remember that all physics that we believe to govern black holes would have to be wrong for us to even begin to worry about such a scenario. However, we want an argument like the cosmic ray argument that doesn't rely on any assumptions at all.

The argument goes as follows:

High energy cosmic rays don't just hit earth, they hit all other things in the universe. So there are high energy collisions with energies greater than the LHC on all objects. Our problem with the earth is that a created black hole could theoretically pass straight through the earth and leave no trace. Therefore we need to find an object where a cosmic ray created black hole would stop rather than pass straight through. Such things exist. They are called neutron stars and are the densest objects in the universe. They are so dense that a black hole would certainly not pass straight through, but would stop instead. This would mean that neutron stars would be eaten by black holes.

Now we see a lot of neutron stars out there and we know how old they are. We can therefore out limits on the speed that any captured black hole would grow to a size at which it would be a danger. It turns out that even if all we know is wrong and collisions of these energies can create stable black holes then such black holes would have to grow so slowly that they would pose no threat to the earth until well after the sun had exploded - by many orders of magnitude.

It was very interesting to hear a long and detailed analysis of the risks from someone who has had to do the work and stand up and argue it in front of lawyers and politicians who are concerned about the risks. And the seminar was followed by pecan pie, which is always a plus.

RPMiller
11-19-2008, 04:59 PM
Mmm... pie.... what? Oh, yea, that other stuff is great news! ;) :D

torstan
02-18-2009, 08:58 PM
So there have been a few developments recently that are worth mentioning. The full story of the CERN magnet failure has come to light. A large helium leak wrenched apart some very large and expensive pieces of machinery. The valves that were supposed to stop this just couldn't deal with the pressures involved. As I understand it, the plan is to replace the ones that were failing and improve the monitoring systems. This will take them through the summer and the LHC won't be starting up until September. They expect to get first collisions - still below the full energy of the machine - in late November, early December I think. They will then run through the winter which is more expensive as the electricity prices go up. However this will give them an opportunity to produce data people can get to work on, and start the all important work of getting the machine to full energy with a tightly focused beam.

In response to this, the tevatron - currently the highest energy collider in the world, and a US endeavour - said they hope to find the Higgs boson before the LHC can be competitive. The project manager for the LHC estimated that the tevatron had about 2 years before the data from the LHC swamps the total data the tevatron will have taken. That gives a pretty good estimate of the amount of time before the LHC produces interesting results. We may get hints and rumours before then though.

The other developments recently have been that the ATIC experiment that claimed in November to have seen dark matter might well be disproved by a new NASA satellite that's been taking data for the last 9 months. This is good news for me as it would mean my theories were not disproved. All good news on that front :)

Just thought I'd drop in a short update for those that have been keeping up with this thread. I'll mention other things as and when they pop up.

Ascension
02-18-2009, 09:53 PM
I, for one, always like to hear the news on what you guys are doing. Fascinating stuff.

Steel General
02-19-2009, 08:04 AM
I agree...even I don't understand the majority of it.

torstan
02-19-2009, 02:07 PM
Well, as always, feel free to ask questions about the bits that I don't explain properly and I'll try to be clearer.

Oh, here's the picture from the BBC of the damage at one of the magnet junctions:
http://newsimg.bbc.co.uk/media/images/45483000/jpg/_45483688_cern_cern_466.jpg


Note that this should all be in a straight line for the particles to travel around the ring. That helium leak really made a mess.

Karro
02-19-2009, 02:21 PM
I'm curious, and maybe this was posted upthread and I missed it, what was your theory that may or may not be disproven based on whether or not ATIC had seen dark matter (and who is ATIC?)

Also, your previous post on the issue of why the earth won't be swallowed in a black hole made in the CERN labs is somewhat disappointing. Now we have to figure out how to spawn a post-apocalpytic setting all-over-again.

jfrazierjr
02-19-2009, 02:49 PM
Well, as always, feel free to ask questions about the bits that I don't explain properly and I'll try to be clearer.

Oh, here's the picture from the BBC of the damage at one of the magnet junctions:
http://newsimg.bbc.co.uk/media/images/45483000/jpg/_45483688_cern_cern_466.jpg


Note that this should all be in a straight line for the particles to travel around the ring. That helium leak really made a mess.


Heh... it's "accidents" like this that don't really engender feelings of confidence that this thing won't end up destroying the world.....:P

torstan
02-19-2009, 04:06 PM
@Karro I'm not sure there would be a lot of world left to be 'post-apocalyptic' if a black hole ate it. What we really need is a disaster that 'just' does serious damage to the planet, without destroying it and/or the accompanying universe.

The theory I work most with is called supersymmetry and it works really well if there are new particles and the lightest new particle is around 100 times heavier than the proton. This is within the reach of the LHC and they would be produced in the lab in numbers that could be measured. They should already be produced very rarely by the tevatron, but their event rates would be so low that they would never see them.

The lightest of these new particles is the dark matter candidate in these theories. Now dark matter is the most prevalent form of matter in our universe, and holds the galaxy together. It interacts very rarely. However, it is possible for one dark matter particle to annihilate with another dark matter particle. In this case you would get two high energy 'normal' particles out, like an electron and a positron. They would each have an energy equal to the mass of a dark matter particle. When the dark matter particles annihilate their mass goes to energy through E=mc^2, so we know the energy of the produced particles. A number of experiments have been looking for these high energy particles.

Now the experiment ATIC (Advanced Thin Ionization Calorimeter) and the PAMELA satellite both claimed to see high energy particles. To cut a long story short, ATIC saw electrons with an energy up to 1000 times the proton mass. Now, you'll see that's 10 times larger than the masses I would like to see. Not only that, but that would set the mass of the lightest new particle. All the other more exotic particles would be heavier. It would be very bad if this were the case. Thankfully the ATIC data seems likely to be disproved so I can breath a little easier and get back to analysing how supersymmetry would show up at the LHC.

@Joe I noticed the quotes around 'accident', which rather suggests you know it was something more than that. Come clean. I know you did it. If you come quietly, I promise to make it swift and painless. If the experimentalists get to you first I can't help you...

Karro
02-19-2009, 04:39 PM
Supersymmetry...

It sounds like beautiful math. Sadly, calculus and the accompanying calc-based physics is as high as I ever got in college on this stuff. I was smart enough to do very well there, but perceived myself to be a half-tic not-smart-enough to go any further down the path of SCIENCE. So I sold out... got a business degree instead. (What I really wanted to do was write :()

Ah, but we fantasize, and a word like supersymmetry is just the sort of thing that sci-fi is made of! Beautiful, elegant, and I have no idea what it means.

Also... I suspect that Joe did what he did...









....with MIND BULLETS.

jfrazierjr
02-19-2009, 05:08 PM
@Joe I noticed the quotes around 'accident', which rather suggests you know it was something more than that. Come clean. I know you did it. If you come quietly, I promise to make it swift and painless. If the experimentalists get to you first I can't help you...

I will quote from one of my all time favorite shows: Hogan's Heroes:


Sergeant Schultz : I know Nooothingg....

torstan
02-19-2009, 05:16 PM
Yes, there seems to be a very deep set of relations at the heart of physics that are based on symmetries like those of shapes, for example a circle has a continuous rotational symmetry whereas an equilateral triangle has a discrete rotational symmetry (you can only rotate it in angles of 120 degrees if you want it to look the same after the rotation). An analagous mathematical formalism describes how different particle states can be related to each other - so you can 'rotate' between particles if they fall within the same symmetry group. It's very clean and powerful but it does tend to screw with your head.

Supersymmetry takes these symmetries one step further and relates the class of particles that photons belong to to the class of particles that electrons belong to. This doubles the number of particles in the theory and gives us lots of new particles to look for. All because we added an extra symmetry to the theory.

Yep. The Mind Bullets. I didn't want to mention them here for fear of attracting Official attention to the thread but I fear Joe's involvement may well be out of the bag now. Ah well, he was a good CL when we knew him.

Karro
02-20-2009, 09:31 AM
Yes, there seems to be a very deep set of relations at the heart of physics that are based on symmetries like those of shapes, for example a circle has a continuous rotational symmetry whereas an equilateral triangle has a discrete rotational symmetry (you can only rotate it in angles of 120 degrees if you want it to look the same after the rotation). An analagous mathematical formalism describes how different particle states can be related to each other - so you can 'rotate' between particles if they fall within the same symmetry group. It's very clean and powerful but it does tend to screw with your head.

Supersymmetry takes these symmetries one step further and relates the class of particles that photons belong to to the class of particles that electrons belong to. This doubles the number of particles in the theory and gives us lots of new particles to look for. All because we added an extra symmetry to the theory.

Yep. The Mind Bullets. I didn't want to mention them here for fear of attracting Official attention to the thread but I fear Joe's involvement may well be out of the bag now. Ah well, he was a good CL when we knew him.


Hmm. That kind of makes sense in a pop-sciency kind of way. Thanks.

Joe: Sorry I ratted you and your secret powers out.

Steel General
02-20-2009, 09:48 AM
Hmmmm....I had Joe pegged as working for the Dharma Initiative ;)

jfrazierjr
02-20-2009, 10:11 AM
Hmmmm....I had Joe pegged as working for the Dharma Initiative ;)

Heh.. I was once known as Dr Marvin Candle....

That reminds me, I was watching the credits for Survivor last night and there was something one there at the end for something like :

Dharma Creative blah blah blah.....

I just found that rather ironic...

RPMiller
02-27-2009, 01:32 PM
Joe, just remember this word: FNORD.

Oh crap, I'll have to say it again as you will have forgotten it after reading. Remember this word: FNORD.

Hm... I don't think this will work after all. Nothing to see here, move along. ;)

jfrazierjr
02-27-2009, 02:15 PM
Joe, just remember this word: .

Oh crap, I'll have to say it again as you will have forgotten it after reading. Remember this word: .

Hm... I don't think this will work after all. Nothing to see here, move along. ;)


What word? your talking nonsense now.... What word should I remember(and why)?

RPMiller
02-27-2009, 02:19 PM
Exactly. :D

Nomadic
02-27-2009, 03:36 PM
Sure it has the possibility to uncover the truth behind the Higgs Boson... but can the LHC uncover the fnords?

jfrazierjr
02-27-2009, 03:49 PM
Sure it has the possibility to uncover the truth behind the Higgs Boson... but can the LHC uncover the ?

Uncover the WHAT???? WHY ARE PEOPLE WRITING INCOMPLETE SENTENCES TODAY???????? argh!

Turgenev
02-27-2009, 03:54 PM
Chorus: "FNORD! FNORD! FNORD! FNORD! Lovely FNORD! Lovely FNORD!"

Waitress: "Bloody Vikings!"

:lol::lol::lol:

RPMiller
02-27-2009, 04:01 PM
Uncover the WHAT???? WHY ARE PEOPLE WRITING INCOMPLETE SENTENCES TODAY???????? argh!
What were talking about?

torstan
02-27-2009, 04:16 PM
Fnord is old school as it can sometimes be circumvented by newfangled technology. These days it is that those who shall not be named use for their dark plans.

joão paulo
02-27-2009, 04:32 PM
Where they want to go with it ?

torstan
05-04-2009, 10:25 AM
So apparently the LHC has been fixed - just in time for the release of Angels and Demons. I'm sure there's no coincidence there... I predict we'll see a small flurry of CERN stories over the coming months. There's a new one today on Yahoo! UK:

http://uk.news.yahoo.com/4/20090504/twl-big-bang-machine-fixed-41f21e0.html

A few choice lines:

Engineers have fixed the "Big Bang" machine after an electrical fault led to it being shut-down in September last year.

Well I guess electricity and electronics were at fault, but I'd say "explosion" would be closer to the mark. Good to know it's pretty much nailed now. The next 4 months will be taken up with cooling and testing of the machine so that they can hit the September restart.

On the subject of Angels and Demons I hear that ATLAS - one of the detectors at the LHC - has been pressed into use as a bit of set for the film, masquerading as an antimatter creation machine. It'll be nice for the experiment to get a bit of Hollywood glamour :)

On the dark matter side, new data released by the Fermi/Glast satellite over the weekend has thrown all models out of the window. Back to the drawing board for structures of dark matter this week. The race is on to fit the new results.

And that's all for this months update. And oh, just to keep us all up to date with events, and for nostalgia's sake:
http://hasthelargehadroncolliderdestroyedtheworldyet.com/

RPMiller
05-04-2009, 10:37 AM
Thanks for the updates T. It is also great to know that the LHC has not ended the world. I'm thankful that that site is up to let us know when it happens.

torstan
05-04-2009, 10:41 AM
I believe it even has an rss feed....

RPMiller
05-04-2009, 11:07 AM
Yes it does. I was subscribed to it at one point, but unsubscribed when the LHC went down. Figured it was no longer necessary to be warned if it wasn't running.

NymTevlyn
05-04-2009, 11:39 AM
New data from the LEHC (Low-energy home collidor):

http://www.youtube.com/watch?v=y-7XwboOx98

torstan
05-04-2009, 02:08 PM
That's pretty cool :)

Here's a shot of someone fixing the magnets:
http://atlas-service-enews.web.cern.ch/atlas-service-enews/images/gallery/photo4_580.jpg

I just love the way you can only just see the curvature of the tunnel.

Ascension
05-04-2009, 05:05 PM
That was freakin cool Nym, nice find.

RPMiller
05-04-2009, 05:11 PM
...other than the spam-age in the description, yea, the guy definitely knows how to create some very cool special effects. I'm curious what software he used to create it because it is definitely professional grade CGI for sure.

RPMiller
08-10-2009, 11:31 AM
We haven't had any news in awhile so I thought I would give it a little bump and also put up a diagram of the ATLAS detector for everyone's amusement.

töff
08-10-2009, 11:46 AM
Recently I was pondering (again) the concepts of faith & knowledge, with a view toward the endless (and absurd) "science vs. religion" war. It struck me that black holes are a prime example, on the scientific side, of faith. Think about it: we can't see them. We can't even get near them (assuming they exist). We only assume, because of thought experiments (call it math if you like), that they must exist, because we see some things that we can only explain if there's such as thing as a black hole, with such-and-such characteristics, causing those secondary phenomena to occur.

... does that sound like God?

For the record, I'm a devout atheist (not anti-religion, though!), and I pretty much do believe in black holes, and I pretty much think that the scientific method leads to truth.

But again ... that's faith, isn't it. The "other side" (those of religious faith) are doing exactly the same thing.

Karro
08-10-2009, 12:06 PM
Recently I was pondering (again) the concepts of faith & knowledge, with a view toward the endless (and absurd) "science vs. religion" war. It struck me that black holes are a prime example, on the scientific side, of faith. Think about it: we can't see them. We can't even get near them (assuming they exist). We only assume, because of thought experiments (call it math if you like), that they must exist, because we see some things that we can only explain if there's such as thing as a black hole, with such-and-such characteristics, causing those secondary phenomena to occur.

... does that sound like God?

For the record, I'm a devout atheist (not anti-religion, though!), and I pretty much do believe in black holes, and I pretty much think that the scientific method leads to truth.

But again ... that's faith, isn't it. The "other side" (those of religious faith) are doing exactly the same thing.


QFT.

I am both a non-atheist (i.e. I have a strong religious faith) and a believer in science (including such general truths as evolution, which seems to be a particular flash-point among some religionists, whereas I find the concept of evolution to be divinely sublime, and in no way denigrates my existence as a human being). I find both requires a certain type of faith - especially as a non-scientist, per se (as in... not beyond the simple experiments you can run in a freshman college physics class) although I think the nature of that faith, between the two, differs. I think my religious faith is testable, in a "scientific"-like manner, where the testable results are feelings and emotions, and not exactly precisely quantifiable. Scientific faith, obviously, is also testable, but the testable results are precisely quantifiable, and appeal to logic as opposed to emotion. Still, as a human being, I find emotion insepperable from my experience and understanding of the world.

torstan
08-10-2009, 12:10 PM
I have to disagree with that (well I would have to wouldn't I :) ). There are certainly good points in what you say - there's an interesting discussion to be had about the foundation of our belief in the way science approaches the truth. However let's start a little earlier. So to start off with there's a clear difference between the scientific method and religion in that if there are two scientific theories about a phenomena then there will be a test that would tell you which scientific theory is correct or whether neither is correct. In the case of religion, if there are two separate religions explaining a phenomena then there will be no tests that can be done to tell which of those religions is correct as the foundation is purely that of belief rather than empirical test.

The two approaches are founded on separate bases from the start.

Black holes are a prediction of general relativity, which has been experimentally tested (and continues to be tested) against other theories. Also explanations of phenomena using black holes are experimentally tested against other hypotheses for the mass at the centre of galaxies. If it turned out that those tests failed then the scientific community would be forced to give up on the concept of supermassive black holes holding galaxies together. These sorts of changes do happen, and surprisingly often. However the black hole hypothesis has been tested many times and found to be a consistent explanation of the phenomena so it is still our current best description of that reality. That's equivalent to saying that we know they exist.

There's some other interesting stuff going on in this field too, but let's talk about this for a bit first.

Karro
08-10-2009, 12:21 PM
snip.

But here's the thing: for us lay-persons who can't actually do science, or sometimes even necessarily understand science... we can't prove or test directly whether any given scientific theory is correct. Those of us who believe in the scientific method/process but can't prove it directly for ourselves have to take it as an article of faith that what those of you who can, the scientists, are telling us the truth. The simple-to-explain parts of it... seem to make sense and jive with what is observable about our world, so we roll with it. In that sense... science, from the perspective of the masses, is exactly like religion, and scientists are it's "priestly" caste.

Most of us approach religion in the same manner - none of us (at least no one I have talked to) has ever seen God/Allah/Deity-of-your-choice directly. Our experience of the world, though, seems to suggest the existence of a higher power... having no ability to test that theorem directly, we rely on the understanding of those who have a greater knowledge of deity.

But you're right, on a macro-scale, we can't prove that one competing religious "theory" is any more correct than another. From my experience, the provability is at a very personal level: do I feel that one religious doctrine is more true than another. It's a science of the heart, but it's very personal. Still... I happen to believe that one particular religious doctrine is the most correct/true of all available doctrines, but I can say that I don't think, logically, that I have the authority to say to another person that the doctrine s/he follows is incorrect - beyond my own personal experience I have nothing to offer as direct evidence of such a statement. So... no... they're not exactly the same... but there's still an overlap in the way we lay people experience it.

That being said: keep up your good work sciencing.

töff
08-10-2009, 12:24 PM
I think you'll find a lot of Christians saying that the Trinity is a consistent explanation of why many phenomena occur, and so that's equivalent to saying that we know Christ exists.

Scientists can apply science to disprove God.
Christians can apply doctrine to disprove science. (Yes they can; some specific aspects of it, anyway.)

Once you get into such details, you've already chosen a side, and that choice dictates your entire paradigm.

But if you step back and think OUTSIDE that choice (objectively, if such a stance is really possible), there's this amazing parallel. And I think that recognizing that parallel can lead to a greater understanding of the "other side."

Yes, I know, science and math and empirical evidence are, to us non-religious types, "PROOF" of our beliefs. Belief becomes "fact." ... But it's the same thing for religion. To the faithful, doctrine is "PROOF" -- it's fact.

From either side, the other side looks absurd and misguided. But the absurdity, running both ways, is parallel. I think that's amazing.

töff
08-10-2009, 12:35 PM
if there are two scientific theories about a phenomena then there will be a test that would tell you which scientific theory is correct or whether neither is correctThe incompatibilities of quantum mechanics vs. relativity is a really good place to start with this idea. They've both been "proven," but they disprove each other. The GUT eludes us, so far.

torstan
08-10-2009, 12:36 PM
I would never ever consider religion to be absurd. I also do not find religion and science to be in conflict. I heard somewhere that the proportion of people with deeply held religious beliefs is actually higher in physicists than average. I'll address the other points in an hour or so, but right now I need to eat lunch.

töff
08-10-2009, 12:40 PM
I guess my point is, a friend of mine declared quite absolutely and vehemently that "science is not a belief system." But I think it has to be. It's a way of perceiving reality. But it's also quite incomplete and uncertain in many ways.

Sure, scientists chase after "truth" rather than philosophical doctrine -- they declare something to be a "theory" and they apply tests and interpret evidence in the hopes of disproving it ... but eventually they give and and say, "Okay, this is a LAW. It's scientific FACT." And they have every reason in the world to believe it.

... to "believe" it. Within science and math and logic, some things just can't be argued.

Once again, I believe it, too. This is my own personal approach. I'm not saying it's wrong.

I'm just saying, it really boils down to a belief system.

And the religious faiths, in so many ways, work exactly the same way.

töff
08-10-2009, 12:48 PM
I would never ever consider religion to be absurdMe neither ... even Heaven's Gate, which almost the entire world calls bizarre and insane and absurd and tragic. But many people of the scientific approach do consider even the world's oldest and most "refined" ("evolved"?) faiths to be built on concepts that are scientifically absurd.


I also do not find religion and science to be in conflict.We can point to scientific or religious concepts that are in findamental conflict with the other side. But I don't want to start the war here all over again.

töff
08-10-2009, 01:02 PM
Another attempt at expressing my idea ...

"Fact" is the endpoint of a line of "belief."

Nothing we conceive can reach that endpoint. We might THINK it does -- something we "believe as fact" might feel as if it's 100% true and factual -- but it seems more realistic to place each of our beliefs somewhere along the line. Some points on MY line (the points will be elsewhere on yours):


The "law" of gravity? 99.99999% -- this one's a really accurate perception, I think.
Black holes? 99.9%
Saddam's WMD programs? 99% (see Halabja, where he used a chemcial WMD).
The magic bullet that killed Kennedy? 50%.
A god (or something else) behind the comet that the Heaven's Gate people were shooting for? 0.0001% (not zero).

But if we can't ever get to that 100% endpoint of "fact," then EVERYTHING IS A BELIEF. Our perceptions and interpretations of reality are never certain. We all just believe things. Sometimes we can't see the gap between 99.9999% and the endpoint ... and so we think we "know" something. And that seems absolute. It seems like the endpoint. We just KNOW it's true.

Ask a scientist about black holes, and she'll say she KNOWS they exist. They have to, according to the sum of all the things that are our world. Has she ever seen one? No (except in her mind).

Ask a Christian about God, and she'll say she KNOWS He exists. He has to, according to the sum of all the things that are our world. Has she ever seen Him? No (except in her soul).

We place beliefs on the 100% endpoint, and call them fact.

Karro
08-10-2009, 01:10 PM
We can point to scientific or religious concepts that are in findamental conflict with the other side. But I don't want to start the war here all over again.

Not to belabor an argument, if there has been one, but do you mind terribly sharing your opinion on where these fundamental conflicts exist?

As a believer in both science and religion, I am unaware of any fundamental conflicts that I have been unable to resolve to my own satisfaction.

töff
08-10-2009, 01:31 PM
sharing your opinion on where these fundamental conflicts exist?Adam & Eve vs. Lucy, for example; whence cometh Original Sin per Darwin?
unaware of any fundamental conflicts that I have been unable to resolve to my own satisfaction.Then you are fortunate to be aware of threats to your belief system and to have avoided or decided them. Not everyone is so fortunate.

***

I just wanted to say this, to those who, like I do, believe in science:

Think about what we "know" and what we believe. Think about black holes ... think about the elusive GUT. Think about the nature of empirical "fact" and "law" in the framework of interpreted perceptions.

Perhaps you, like I have done (to some degree, I hope), might gain an insight into religious faith, which, for so many people who share our science-based outlook, can seem (and often is) irrational and naïve and blind and science-antagonistic.

I say this in the hopes that someone might gain a new perspective on the barriers that divide us within the human race ... barriers that have led, least case, to misunderstanding and separation ... worst case, to murder and war and horror.

torstan
08-10-2009, 01:50 PM
@Karro: That's a very good point. Many scientists do just say 'I've tested this' or 'I've researched this' and so you must believe it to be true, without any consideration for the level of belief that engenders. That certainly does have parallels with religious belief where people are required to believe something on the word of someone else.

The issue that should be made clear is that tests are done, and that theories are measured off against one another. If it can't be disproved then there's an argument for saying it's not science. That's unique to science and holds it apart. I would never hold any religion to that standard - that would be crazy. That's at the heart of the difference between the two fields. Whilst that difference exists I have to disagree that the two are the same.

Now, on to Toff's point.

Science cannot disprove God and should never try. If you take a view that a deity of a religion is omnipotent then any argument you place against the existence of a deity is flawed as any evidence (including your own logic) is based in the world created by and manipulated by that deity. Therefore there is no logically consistent way science can prove or disprove the existence of an omnipotent deity.

Religion cannot disprove science either and shouldn't try. Say I hold a deep religious belief that God causes all objects to fall down. Now a scientist says that gravity causes objects to fall down. Now say that in one bizarre turn of events an object does not fall down. A scientist says that his gravity theory is wrong. The person with the religious conviction says that God decided that the object wouldn't fall down this time. Is that a disproof of the science? No. The omnipotent God can cause the object to move in any way. This means that the hypothesis cannot be proved or disproved. The scientist accepts that the empirical evidence (not the religious theory) has refuted his theory so he goes away and does more tests to formulate a consistent theory that incorporates the new phenomena. That theory will have testable consequences that the scientist (if he has any rigour) will go and attempt to test.

There are many instances where there have been conflicting scientific theories proposed that are motivated by religion. But the debates have been settled through the scientific method rather than an appeal to belief.

Right, before Toff jumps in I need to address the core of his argument, which I've been skirting up until now.

How do we know the scientific method has any bearing on the way the universe works? We don't. It is a belief, and one that is at the heart of science. This is the place that science and religion do cross paths. Both are founded on the basis of belief. The difference is in what those beliefs are. In science the beliefs are of the form of things such as:

1. There are laws that the universe obeys. If something happens time and time again there must be a very good reason if it suddenly does something different. That reason will also be some form of rule or law that if the same scenario were to repeat, the theory could predict the behaviour accurately. This is essentially a law of inductive reasoning.
2. It also requires that we trust our interaction with the world. Essentially this is Descartes Evil Demon argument (or the brains in vats of the matrix). We cannot prove that the world is not an illusion presented to us by some omnipotent malign intelligence. Therefore we must believe that this is not the case and act accordingly.

Now on the basis of these two principles we can make enormous progress, and make sensible informed decisions.

Religions have very different core beliefs which define how relative decisions are made about the explanations of the world we experience.

These two sets of beliefs define how we make relative choices between explanations. If you apply the criteria of choice at the heart of science to two religious explanations then you aren't having a religious debate any more. If you apply religion's decision making criteria to a choice between two scientific theories then you aren't doing science. This is a clash of paradigms (as introduced by Thomas Kuhn) just as Toff mentioned.

This is why (I believe) there will always be conflict between the two, and also why I feel that the two sides are not actually in conflict.

Sorry for the long post, but I hope it was an interesting read. Right. Off to see if I can make some falsifiable predictions now.

Karro
08-10-2009, 01:51 PM
Adam & Eve vs. Lucy, for example; whence cometh Original Sin per Darwin?


Ahh. So these examples are doctrinaly-specific conflicts, and not general in nature. (As a for-instance, the doctrine of my church of choice rejects the concept of Original Sin and has what I might characterize as a somewhat nuanced view of Adam & Eve.)


Then you are fortunate to be aware of threats to your belief system and to have avoided or decided them. Not everyone is so fortunate.



Thank you; yes, I think that I am fairly fortunate. Howbeit... I don't think I have specifically avoided threats to my belief system. I'm actually a religious convert, consquent to just such threats to my belief system that, once resolved, required for me a change in my church of affiliation.