Will the LHC Smash Supersymmetry?

gbrumfiel writes "The Large Hadron Collider is just getting ready for its next big science run. One thing researchers hope it will find is evidence for supersymmetry, a theory that could help to unify fundamental forces and explain mysterious dark matter. But as Nature reports this week, the LHC has shown no signs of supersymmetry in data from last year's run. If super particles don't appear by 2012, then physicists might give up on the theory for good."

Comments

A validated theory is a stepping stone ...

[perpenso]

Suppose they prove super-symmetry and find the Higgs Boson, what are we going to be able to do with it. Other than completing the theory, is there any practical use for this new found knowledge? Genuine question, physics isn't my forté. Thanks,

A validated theory is, if nothing else, a stepping stone to an even more complete understanding. From better understanding comes new, or improved, tools. There is sometimes a time lag between discovery and practical application. Sometimes decades, sometimes a century or more. Consider nuclear fusion (what the sun is doing), potentially a safe and abundant source of power. Figuring out how to build and operate a fusion reactor will require understanding a few theories that were at one time merely theoretical with no practical application.

Re:A validated theory is a stepping stone ...

[thesandtiger]

The question then that I would have is "Why don't people who are trying to come up with practical applications act 'as if' the theory were true?"

I guess what I'm getting at (I'm not the AC who started this but I am also in a similar boat, understanding-wise) is: Right now it seems that most physicists THINK this theory is true. If that belief is validated, okay, great, they know they're on the right track, but aren't they already basing a lot of ideas for steps further down the line on the notion that this might be true? And, if that's the case, then aren't people coming up with, or at least thinking about, practical applications based on that assumption?

To me, it seems like the really interesting result would be if this assumption of super-symmetry (or anything else in a particular theory that is widely believed) doesn't actually prove true or doesn't behave like it has to for the theories to be true.

In case I'm being obtuse, I'll use an analogy:

When people were making rockets, they had some theories about what might happen in space, or what might be needed for the rocket to work, or what might happen to the people on a rocket, etc. They behaved "as if" those theories they had were true, or, at least, "as if" the most risky/dangerous versions of their theories were true and designed accordingly. So, they launched rockets, people were in them, and some of their theories panned out, some did not.

What could be built if these theories are true?

And, I am totally 100% behind the idea of learning stuff just to learn it - even if there isn't a practical application, understanding the universe is important.

Bleh, sorry, sick as a dog and on massive doses of NyQuil so I ramble.

Re:Naive Question

[TaoPhoenix]

Didn't we have the same "what use is this" question after that math story the other day? It's like a oblique troll that something is Useless Until Proven Useful.

General Theory of Truth: If something is true, something cool can be done with it. No exceptions. Politics don't count.

I agree *you* don't need this, but someone out there has to know this stuff.

Re:Naive Question

[darenw]

That's like going back in time and asking Coulomb or Volta about what applications their research would have.

"I don't know. Well, if you could make a small enough electrochemical cell to hide in your pocket, with wires you could shock people when you shake their hands, as a practical joke. Hee hee."

One way supersymmetry would be useful is at the theoretical level - it gives particle physicists another mathematical tool for predicting yet other kinds of particle to hunt for. It might help with understanding dark matter. When we know enough about space time matter and energy, my secret hope is we'll have insights for building faster than light insterstellar ships, or something else awesome.

That's what's wrong with Physics today

[gr8_phk]

It's not enough to find the Higgs and confirm the standard model. No, we must always be looking for strange new shit that violates the laws of physics as we know them. New particles, new types of matter, dark energy, broken symmetry, anything unusual. And if it can't be proven so much the better. Yes, I'm still waiting for them to realize that Keplers laws do not apply to galaxies, and the galactic rotation curve does not require dark matter to explain. Some of them also fail at application of the divergence theorem when it come to gravity (they basically assume any mass distribution can be treated as a point mass). Let's get the fundamentals right first before we run off looking for actual violations of the laws of physics please.

Re:That's what's wrong with Physics today

[Mr_Huber]

Er, they do realize that Kepler's laws do not apply to galaxies. They cannot, in fact, use Kepler's laws because they know quite well that the gravitational contribution of the stuff orbiting the center of mass is significant. That's why they use Newtonian physics in this situation. Our modern understanding of the evolution of spiral arms comes from this sort of analysis. They do not use Special or General relativity in this situation for two reasons. First is that the math is real hairy. Second, at these speeds and distances, it reduces down to good old Newtonian motion anyway.

As for Dark Matter, yes, there was a flash in the pan article a few years back about someone using General Relativity to analyze rotation curves and coming up with enough extra contribution to invalidate dark matter. The paper was up on ARXIV for about four hours before the first math errors were spotted and brought the whole thing crashing down. And even if that paper held, it wouldn't have explained results like the Bullet Cluster (http://en.wikipedia.org/wiki/Bullet_Cluster), where maps of particulate dark matter have been made. No modified gravity theory or assertions that dark matter goes away under SR or GR can explain those findings. Dark matter is real and we now have tools with which we can spot it. The trick is now to figure out what it is.

You seem to have a real misunderstanding of how physics, and all science, makes progress. Once we have theoretical models, they are, generally, perfect. A good theoretical model explains ALL available data, or it isn't a good model. Once we have a good model, the only way to improve it is to go actively looking for where it diverges from reality. Only with this new input, divergence from theoretical predictions, can models be refined, improved or even replaced.

That's why we're hunting the Higgs particle. Fact is, the Standard Model is slightly broken. Without a Higgs mechanism, predicted lepton mass does not conform with experiment. We have a gap right now, a discrepancy. We think we have a solution in the Higgs field. We could, I suppose, assume there's a Higgs field, pick one of the several variants and go with it. Or we could, you know, do some actual science and go looking for the thing and nail down its properties. Along the way, if we see some of the other things we're half expecting, super symmetry, discrepancies in gravity at the millimeter range, broken symmetries, energy leakage at high energies or anything else, so much the better.

The problem with science is not a lack of fundamentals. The problem is the theories are too damned good. Reality simply does not diverge from the theories unless we get into some really exotic conditions. Why do we need a superconducting particle collider with a diameter measured in kilometers? Because our models are frikkin' perfect for everything up to that. We know they're wrong. We know we can't reconcile GR with the Standard Model. But we won't know how to proceed until we can break either GR or the Standard Model. We don't know what piece of the puzzle is missing until we actually go and look at things.

Re:Naive Question

[The_Wilschon]

Here's one possibility: All of our favorite science fiction stuff (things that would allow us to effectively have a galactic or even universal civilization) appears to be disallowed by special and general relativity. However, these things necessarily break down in some regard at the smallest (ie highest energy) scales. Understanding quantum gravity (if we can ever do so) will tell us just exactly how relativity breaks down at super high energies. It is possible that the particulars will show us a way to travel and communicate faster than light (think things like the Alcubierre bubble).

The LHC will probably not unlock the secrets of quantum gravity. However, understanding the lower energy phenomena like the mechanism for electroweak symmetry breaking, or supersymmetry (or technicolor, or a variety of other speculative theories) is a necessary step towards understanding quantum gravity. As such, I think that experiments like the LHC are vitally important to the extremely long term survival of the human species (we have to get off Earth and out of the solar system sometime within the next few billion years, at the very least).

As other posters have pointed out, this, along with all other speculative applications of what we learn from the LHC, are probably not going to be seen during our lifetimes.

Re:Naive Question

[John Hasler]

What we do know is that pure (or basic) research often enable progress in more practical oriented research.

Nuclear weapons, to be exact. Science brought politicians the bomb. They've been throwing money at physics ever since in hopes of something even better.

Good way to waste time

[Roger W Moore]

The question then that I would have is "Why don't people who are trying to come up with practical applications act 'as if' the theory were true?"

...because that would be a very good way to waste a lot of time. First question is "which theory" do you take to be true? Simple Standard Model Higgs or a Supersymmetric Higgs, or even a 2-higgs doublet model without supersymmetry? Next question is what is the mass of the Higgs bosons in your accepted theory? The problem with any unknown model is that there are free parameters which are unknown and so the phase space opens out so fast that it becomes impossible to concentrate any amount of effort on one particular area.

The other problem is that any effort may be completely wasted. For example Columbus set off to find a passage to India. Had you attempted to set up an Indian spice importing operation before he had returned you would have looked like a complete idiot.

Utility is part of the plan

[Roger W Moore]

Physics at this level is like abstract mathematics: it exists for its own sake. Practical applications of this physics is like practical applications of number theory: just not in the plan.

Completely wrong. I don't know a single physicist who believes that. The reason we do what we do is because we are curious about the universe and want to find better ways to exploit it...but the first step in that is understanding. Practical applications are always part of the plan. The problem is that since we don't yet know the physics we don't yet know how to use it practically. 100 years ago "Physics at this level" was quantum mechanics which, since you are reading this article on a silicon based device, has turned out to be extremely useful. Of course absolutely nobody at the time could possibly have predicted the development of the integrated circuit from an understanding of quantum mechanics.

Even today early particle physics detector and accelerator technology is produced better medical imaging and treatment options. Just because we cannot imagine how today's discoveries will be used in 70-100 years form now does not mean that we don't fully expect them to be used for something.