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Will the LHC Smash Supersymmetry?

CmdrTaco posted more than 3 years ago | from the i-can't-even-balance-my-checkbook dept.

Science 196

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."

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196 comments

Naive Question (4, Interesting)

Anonymous Coward | more than 3 years ago | (#35348682)

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,

Re:Naive Question (2)

Rakshasa Taisab (244699) | more than 3 years ago | (#35348804)

Pure research of this kind does not usually have any immediate applications that can be pointed to, so your question isn't exactly applicable. What we do know is that pure (or basic) research often enable progress in more practical oriented research.

Re:Naive Question (5, Insightful)

TaoPhoenix (980487) | more than 3 years ago | (#35348950)

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 (1)

ByOhTek (1181381) | more than 3 years ago | (#35348990)

Politics do count - look at all the lies in politics, obviously politics aren't true. Your rule is not broken, no exception is needed.

Re:Politics (2)

TaoPhoenix (980487) | more than 3 years ago | (#35349078)

Sorry, I wasn't clear.

I meant that cool stuff "can be done". "Whether it will be done" is the whole other problem with the political side. Sometimes the "can be done" is pretty hard, and politicians hate hard stuff. "We can have a moon base in 20 years" - but only if we were so scared we stopped most of our petty squabbling to do it. Seriously, you engineer types out there, how hard is it really to get a quad-protected airtight building to the moon? Put it at some kind of shade-crossover point to use the solar power but not get totally fried.

The problem now is we have a Terrorist meme that will instantly shut down any planetary science because we have decided we can't trust anyone to be on the base without blowing it up.

Re:Politics (1)

ReedYoung (1282222) | more than 3 years ago | (#35349954)

I hear ya. The problem in politics is that what "can be done" generally depends on 50% + 1 of all citizens agreeing that a thing should be done. And even then a minute but extremely noisy bunch of teabagger freaks who the media loves to cover can still be a major obstacle for as long as legislators believe they're significant, because they don't understand and haven't bothered to learn, that the media is ignoring much larger, legitimate grassroots groups (not corporate sponsored) and by and large letting Glenn Beck, et al get away with enormous lies about the number who turnout for his pathetic event, for example.

Sorry, I wasn't clear.

I meant that cool stuff "can be done". "Whether it will be done" is the whole other problem with the political side. Sometimes the "can be done" is pretty hard, and politicians hate hard stuff. "We can have a moon base in 20 years" - but only if we were so scared we stopped most of our petty squabbling to do it.

Ha!

Seriously, you engineer types out there, how hard is it really to get a quad-protected airtight building to the moon? Put it at some kind of shade-crossover point to use the solar power but not get totally fried.

The dividing line between sunlight and shade / "night" on any planet (or moon) is called its Terminator.

Re:Politics (2)

ByOhTek (1181381) | more than 3 years ago | (#35350028)

The politicians are the Terrorists!

Remember kids, if you support a politician, a terrorist wins!

Re:Naive Question (1)

icannotthinkofaname (1480543) | more than 3 years ago | (#35349482)

It's like a oblique troll that something is Useless Until Proven Useful.

Not unlike the user(s) posting the troll post(s), I daresay.

Re:Naive Question (0)

Anonymous Coward | more than 3 years ago | (#35350170)

*cackle* "Who's that walking on my Higgs Boson Bridge?" *cackle*

Re:Naive Question (2)

thesandtiger (819476) | more than 3 years ago | (#35349800)

The troll in that thread was the idiot who didn't even read the summary where the answer to the question he had was given. In this case, I know I (and I assume the AC) genuinely want to understand what exactly this means because of a lack of understanding about physics.

The way I'd look at it is this:

If someone discovers a proof that P==NP, then even though we haven't found the practical solutions to some problems (factorization or whatever) yet, it means that there IS at least one "quick" solution. So, that basic knowledge has that potential practical application - even though we don't know how to do it yet we know it CAN be done, if this were so.

If someone discovers that super-symmetry or the Higgs is true or false, what does that mean? What practical applications, even in theory, would come from that discovery? I know that the basic research is important, but I'm curious as to what it might mean. Would we be able to then say "oh, hey, this means that even though we don't know how to do it, artificial gravity is possible" or time travel or whatever kind of thing?

Re:Naive Question (1)

vegiVamp (518171) | more than 3 years ago | (#35350330)

I'm not particularly up to scratch on high-end physics, either, but you're very much thinking in the right direction, I'd say: proof that a current theory holds it's ground, means you can start looking at the theoretical possibilities that flow from that theory as rather more likely to be possible, which will cause more attention to indeed go towards them, some of which in turn will eventually lead to me zapping to work instead of being stuck in traffic, so to speak.

All knowledge is potentially useful. Sometimes the methods used to obtain it are objectionable (Dr Mengele, for example), but knowledge in itself is always a good thing.

Re:Naive Question (2)

khallow (566160) | more than 3 years ago | (#35350506)

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.

I would use the term "truism" not "oblique troll". I consider the current tired slop, which passes for justification of science, to be abominable. If you do work in the sciences at the behest of someone else, I can only hope that you justify your work far better than what you did here. This is a reasonable question to ask and it is disturbing how frequently it is brushed off.

In the case of figuring out whether supersymmetry is a feature of the universe or not, it is worth noting that advancing fundamental theories of physics have helped us in the past. Quantum mechanics is the basis for the model of semiconductor physics which we have so successfully used to power wave after wave of computers. Relativity led to the discovery of fission, fusion, and a host of subtle effects that affect really precise atomic clocks. Quantum electrodynamics predicted the existence of anti-matter and explains free electron lasers.

Quantum Chromodynamics is the current state of the art. While I can't point to an invention enabled by the theory, the theory does an adequate job of modeling particle jets which are real phenomena experienced by anything which is exposed to very high energy cosmic rays. And it explains all the known particles that we have seen so far.

So justification #1, past success indicates likely future success.

As a result we have something like tens of thousands of people, who incidentally cost a lot to employ, exploring the boundaries of current physical theory. But they have a big problem, not a lot of observational evidence. This leads to justification #2, any new observations trim the thicket of theories and better focus this vast expenditure of society.

Third, it's not a primary target. Justification #3, it's a freebie that you might get from work that was going to be done anyway.

Fourth, we can already think of genuine applications. For example, if you can figure out how to reliably emit, steer, and intercept neutrinos, then you have a potential communication device which can operate through the Earth, even through the Sun. An obvious near future application of that is communication from a central point on Earth to deep sea subs (such as the US or Russia's submarine forces). It also provides a significant communication edge for high frequency traders. It's the only way someone on Earth could directly communicate with someone on the far side of the Moon (which always faces away from the Earth).

The reason this exercise is useful is because we have many ways to decide how to spend the money that gets spent on scientific output. Maybe it could be spent on other things of pressing urgency such as feeding children or marketing a business's existing product (depending where the money comes from). Even if you decide on a scientific expenditure, it is worth recalling that there are more than one possible destinations.

This is why it is important to have justification, one or more reasons why something is useful. Because someone has to decide what to try, even if it's left to the scientist with ideas rattling about in the skull.

Else, you might as well spend all that science money on me, Mr. Khallow. You'll get science (check!) and some really cool block parties, well, nation-scale parties. A bit more money might be spent on the parties than on the science, but that's ok. Science is being done. That's all that need concerns you.

Re:Naive Question (3, Insightful)

John Hasler (414242) | more than 3 years ago | (#35350300)

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.

Re:Naive Question (1)

Even on Slashdot FOE (1870208) | more than 3 years ago | (#35348810)

Honestly, "What can we do with it" generally gets answered after we can prove we have it in the first place, but I'm sure there's at least one theory that says supersymmetry allows arbitrarily awesome things like wormholes or something.

Re:Naive Question (1)

thesandtiger (819476) | more than 3 years ago | (#35349832)

That isn't quite true. For example, even though we don't know if P==NP or not, people have ideas for what could be or could not be done in either scenario. We don't know *how* to implement a quick factorization algorithm, for example, but we know that if P==NP we *could* eventually figure that algorithm out because we would know that it must exist.

And the "theory that super-symmetry allows awesome stuf" is probably exactly what the original poster was asking about, and I'm in the same boat.

A validated theory is a stepping stone ... (5, Insightful)

perpenso (1613749) | more than 3 years ago | (#35348900)

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 ... (3, Insightful)

thesandtiger (819476) | more than 3 years ago | (#35349746)

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:A validated theory is a stepping stone ... (1)

tendrousbeastie (961038) | more than 3 years ago | (#35349910)

There aren't any practical developments that can be made on the assumption that these theories are true.

It takes a £30 billion system like the LHC to even work out that the particles involved in these theories exists. Developing consumer (or otherwise) technology to make use the these particles is not within the reach of any modern organisation.

Good way to waste time (3, Insightful)

Roger W Moore (538166) | more than 3 years ago | (#35350502)

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.

Re:Naive Question (3, Insightful)

darenw (74015) | more than 3 years ago | (#35348970)

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.

Re:Naive Question (3, Funny)

AvitarX (172628) | more than 3 years ago | (#35349142)

I bet it was more along the lines of "A Leyden jar that works more than once", or "Zombies!"

Re:Naive Question (1)

maxwell demon (590494) | more than 3 years ago | (#35349684)

When Faraday was asked by the finance minister what this electricity was actually good for, he answered: "One day you will tax it."

To be precise... (5, Interesting)

Kupfernigk (1190345) | more than 3 years ago | (#35350532)

I'm not even going to apologise for this pedantry, because I was at one time a member of the Royal Institution, before I foresook science for engineering.

In fact Faraday's joke was better than that, It was the Prime Minister (in those days called the First Lord of the Treasury, hence your confusion), and the Government had recently introduced some unpopular taxes. So Faraday's actual reply, "I know not, but I wager one day your Government will tax it" was doubly apposite.

The other one of these Victorian quotes is the response of the inventor of the dynamo when asked what use it was: "What use is a new-born baby?"

Re:Naive Question (2)

Beelzebud (1361137) | more than 3 years ago | (#35348996)

I'm not sure anyone can give you a specific example but look at it this way: Know exactly how and why particles have mass, seems like a fairly fundamental thing to understand about the universe.

Re:Naive Question (1)

jellomizer (103300) | more than 3 years ago | (#35349052)

Well this theory, if proven would be able to give engineers knowledge on more basic rules, and limitations that they can factor into their designs. Just as electricity was discovered it took a fair amount of time for it to be useful for anything, it took the discovery linking magnetism and electricity before anything of use could be invented. Other then that it was used for well just zapping people, and some cool sideshow effects, as most Electrical energy was generated via static electricity, and chemical, which was done on a low enough scale to be useful.

Re:Naive Question (2)

DeCappa (651304) | more than 3 years ago | (#35349116)

What's the use of a new-born baby?

-Benjamin Franklin

Re:Naive Question (5, Funny)

theMoleofProduction (842123) | more than 3 years ago | (#35349154)

Once you find the Higgs there's a cut scene where God kicks in the door at Stephen Hawking's house, pistol-whips a nurse, and wheels Hawking away with a gun to his head. It fades to black and you see: "ACHIEVEMENT UNLOCKED: BOSON-NOVA!" The Level Up screen opens, you get to distribute skill points and pick a Level II perk, and then you move on to the next quest.

Re:Naive Question (1)

theMoleofProduction (842123) | more than 3 years ago | (#35349192)

CRAP! I forgot to add SPOILER ALERT!

Re:Naive Question (1)

SlashV (1069110) | more than 3 years ago | (#35349562)

Hahahaa, I've never laughed so loudly at a /. post. Hilarious :)

Re:Naive Question (2)

ObsessiveMathsFreak (773371) | more than 3 years ago | (#35349760)

...and then you move on to the next quest.

Collect 8 top quarks and 3 anti-hydrogen atoms.

Re:Naive Question (1)

mcelrath (8027) | more than 3 years ago | (#35350466)

You seem to be confused. You need at least twelve top quarks [arxiv.org] .

Re:Naive Question (0)

geekoid (135745) | more than 3 years ago | (#35349168)

If the HIggs Boson exists and create matter, understanding how is function could lead us to be able to create matter in the laboratory.

Also we could create are own universes...well, new universes but we probably wouldn't be able to move into them.

Also, if we can create our own matter, we end our energy crisis.

Of course, that's all way off ideas that depend on the properties of the Higgs Boson. We are human. If we discover something, we will find a use for it because We are that damn awesome.

Re:Naive Question (1)

maxwell demon (590494) | more than 3 years ago | (#35349738)

If the HIggs Boson exists and create matter, understanding how is function could lead us to be able to create matter in the laboratory.

The Higgs boson doesn't create matter. It (or rather the corresponding Higgs field) creates mass. That is, assuming the Higgs model is correct, without Higgs there would be exactly the same particles, but they would be massless.

Re:Naive Question (0)

Anonymous Coward | more than 3 years ago | (#35349184)

you could have asked the same about antimatter. now we have PET scanners. or how about lasers.

Re:Naive Question (0)

Anonymous Coward | more than 3 years ago | (#35349282)

It should allow for unification of all fundamental forces of nature. This will give you control over force, gravity, electromagnetism, matter, etc.

Also, super-symmetry requires some sort of "anti-particle" to go along with every mono-polar particle we see -- including the single electron. It's "anti-particle" is unobservable. Some theories consider this so called "dark matter" to be comprised of all these unobservable anti-particles.

You can think of all the observable particles as being in "real space" and the anti-particles being in "imaginary space". When trying to answer the question of where an electron gets its energy from, you can explore this "imaginary space" for an answer. The electron becomes a simple di-polar broken symmetry at this point. We've observed that broken symmetries in nature are present among all of our forces, potential energies, etc.

Finally, you can discover a super-symmetry thermodynamics that allows for conservation of energy between these "real spaces" and "imaginary spaces". This would not violate any laws of thermodynamics, but would appear to be "free energy" or "perpetual motion" in the observable space.

Re:Naive Question (1)

boristhespider (1678416) | more than 3 years ago | (#35350012)

supersymmetry doesn't unite the forces. you've got to do something else to do that, such as super(symmetric)gravity and super(symmetric)string theory. they're an extra layer (and a good few extra dimensions) on top of a "standard" supersymmetric model such as the minimally-supersymmetric standard model.

Re:Naive Question (3, Insightful)

The_Wilschon (782534) | more than 3 years ago | (#35349288)

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.

Utility (1)

overshoot (39700) | more than 3 years ago | (#35349498)

is there any practical use for this new found knowledge?

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.

Re:Naive Question (0)

Anonymous Coward | more than 3 years ago | (#35349620)

Given that the Higgs Field theoretically delegates mass to objects, I've heard that if we became able to manipulate said field in the future, we could create huge massless structures, and in turn could accelerate to the speed of light with ease.

Re:Naive Question (2)

MightyMartian (840721) | more than 3 years ago | (#35349704)

Basic research rarely has obvious applications, and yet it pretty much lies at the heart of all technological advances. Guys screwing around in the 18th century with Leyden jars doing all kinds of interest parlor tricks probably looked pretty silly on the face of it, as well, and yet the ultimate value of these early experiments was enormous.

Re:Naive Question (1)

ConceptJunkie (24823) | more than 3 years ago | (#35349808)

Other than completing the theory, is there any practical use for this new found knowledge?

Duh! Flying cars, jet packs, bionic limbs, amusement parks on the Moon... all that stuff they've been promising us for the last hundred years!

Seriously though, the stuff this will give us in the decades to come is so cool and amazing that no one has even imagined it yet. Take a look back at harnessing electricity, harnessing nuclear power, discovering relativity and quantum physics and figure out what those things eventually gave us.

Of course, just knowing is itself worth the effort.

Re:Naive Question (1)

tendrousbeastie (961038) | more than 3 years ago | (#35349836)

Its a fair question. Some abstract theoretical physics leads to huge new technologies, some leads to none.

For example, relativity theory (special and general) did not in and of itself lead to any great new machines or devices (although it lead to other developments in physics which did).

Whereas quantum physics lead to loads of stuff, not least lasers and semiconductors and hence modern computers and communications.

The only general rule is that you can't tell if a scientific discovery will have utility until it is discovered.

Re:Naive Question (0)

Anonymous Coward | more than 3 years ago | (#35350154)

GPS uses general relativity to work accurately.http://en.wikipedia.org/wiki/Tests_of_general_relativity

Re:Naive Question (1)

Jamu (852752) | more than 3 years ago | (#35349876)

Your question is premature. Applications mostly come after we've worked out something's nature. Historically, for Physics, the answer is yes, and most of the world's economy will be based on it.

Re:Naive Question (1)

mu22le (766735) | more than 3 years ago | (#35349950)

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?

Nobody knows, but neither did Maxwell 150 years ago when he formuleted his theory of electromagnetism, nontheless without it you wouldn't have radios, ipods or cell phones. Einsten had no idea what his general relativity was good for but without it you wuoln't have GPSs and Li-ion batteries.

I could go on for a while, but let me tell you that real scientists work because they want to understand nature better, regardless of any pratical use that may stem from their work.

Re:Naive Question (1)

Kjella (173770) | more than 3 years ago | (#35350000)

For a practical application, you can just assume the model is correct. For example ancient swordsmiths knew lots about how to make microstructures in steel without ever being able to see it in a microscope. But it didn't matter, because it worked. Nothing directly is held up by this, if something needs supersymmetry to work we could just build it and see if it works.

However, the more you know the more chance you can come up with something intelligent to try. For example it's highly unlikely you'd come up with the idea of a laser without finding out how atoms and photons work. Of course you can do thought experiments but they have their bounds. If we find the Higgs boson and that is responsible for mass, maybe we can manipulate it? There's plenty possibilities but first we have to find it.

Re:Naive Question (1)

osgeek (239988) | more than 3 years ago | (#35350272)

It probably has more practical use than the knowledge that Green Bay won the Superbowl.

Re:Naive Question (2)

MobyDisk (75490) | more than 3 years ago | (#35350312)

IANAP. There will be 1000 responses explaining why I am wrong. But every reply I've seen so far is "it might be useful for some undetermined future reason" which seems pretty weak. So at the risk of technical inaccuracy, here is my speculation:

The Higgs Boson is the particle that assigns mass to another particle. Once we understand it, it opens up a lot of questions and experiments:
- Can we create a Higgs Boson, thus creating artificial gravity? Tractor beams?
- Can we use them for signaling?
- Could we create gravity waves?
- Could we use them to store power?
- Could we create matter with no mass?

Re:Naive Question (0)

Anonymous Coward | more than 3 years ago | (#35350394)

What use is this whole 'Simulated emission of photons?' anyway?

When they first invented the laser they didn't have any use in mind for it either, now it makes a great cat toy. I hear they can even do a few other things with it.

Re:Naive Question (2)

rgbatduke (1231380) | more than 3 years ago | (#35350410)

A more interesting question is what will happen if they don't prove supersymmetry and fail (once again) to find the Higgs Boson, and in fact find "nothing particularly interesting" (perhaps beyond insight into the quark-gluon plasma, which is already forthcoming) all the way out to its maximum energy across all experiments.

Lack of evidence is not evidence of lack, but it is worrisome. It leaves open the possibility that we are off on completely the wrong foot, that reality is really nothing like our models, and we might have to go looking for new physics to consistently explain things like particle mass and gravitation and cosmological deviations from gravitation currently wrapped up in the "dark matter/energy" hypotheses.

Come to think of it, we might learn just as much from failure as from success. As usual. Even if it is a very expensive failure, compared to the knowledge gleaned from it.

rgb

Re:Naive Question (1)

C0vardeAn0nim0 (232451) | more than 3 years ago | (#35350412)

i remember a story about benjamin franklin being asked by fellow congressman what would be the practical uses for electricity. his answer ?

"i don't know what it's usefull for, but i know that in the future you will taxing it".

so, there's your answer.

Re:Naive Question (2)

ironman_one (520863) | more than 3 years ago | (#35350430)

Well, here is a story about a former Italian minister asking Alessandro Volta [wikipedia.org] what "possible could be the benefit of electricity".( At he time electric appliances consisted of the " the Voltaic pile [wikipedia.org] . A device able to give anyone a rather unpleasant chock but not much more.) Well, sad Volta, I relay don't know but sometime you might be able to tax it.

If super particles don't appear by 2012 (0)

Anonymous Coward | more than 3 years ago | (#35348794)

2012 will be the next cycle when a new grand unified theory can get elected. And if we can't get any of these superparticles employed, the supersymmetricals could be on the outs for years to come.

Re:If super particles don't appear by 2012 (1)

Anonymous Coward | more than 3 years ago | (#35348994)

This is a moot point as everyone is aware, the world ends in 2012. Possibly the creation of these superparticles is trigger event, collapsing the entire earth into a 70 mile wide ball of degenerate matter, and finally eliminating Justin Bieber from the universe once and for all.

well if the cubs win it all this year (1)

Joe The Dragon (967727) | more than 3 years ago | (#35349022)

well if the cubs win it all this year (sadly not likely) then look out.

Re:well if the cubs win it all this year (1)

medv4380 (1604309) | more than 3 years ago | (#35349222)

Just as they are about to win time will stop and their win will be unobservable.

Re:If super particles don't appear by 2012 (0)

Anonymous Coward | more than 3 years ago | (#35350084)

It's funny to see how "the end of an era" got badly translated into "the end of the world".

December 21st 2012 is simply the end of the pisces calendar. Get ready for the aquarius calendar!

and then (1)

Krau Ming (1620473) | more than 3 years ago | (#35348914)

Brian Greene can write another book.

high enough energy? (2)

Krau Ming (1620473) | more than 3 years ago | (#35349004)

*warning* semi-naive physics question here: does the LHC smash particles at a high enough velocity (or energy?) to definitively solve these problems? does the absence of a Higgs boson from the previous experiments disprove supersymmetry, or are we not smashing hard enough?

Re:high enough energy? (2)

spottedkangaroo (451692) | more than 3 years ago | (#35349124)

I'm wondering the same thing. I think that they're looking for the "lightest super partner." Even one such partner would be evidence even if most of the partners were too heavy to show up in the LHC. But I don't really know how heavy any of them are.

Re:high enough energy? (2)

boristhespider (1678416) | more than 3 years ago | (#35349240)

most of them are pretty damn heavy. i believe the lsp is expected (from some models of supersymmetry) to show up in the lhc but it's easy enough to make sure it doesn't. if an lsp is found then at least part of the dark matter problem will be found, because that thing's basically stable and doesn't interact with us in any way.

warning: unfocused and off-topic rant ahead.

what's going to upset me is if an lsp is found (which i see as pretty unlikely, in all honesty) people are going to be shouting about how they've solved the dark matter problem -- they haven't, they've found that an lsp exists and is guaranteed to form *part* of the dark matter. there are plenty of other candidates and unfortunately i've been in physics long enough to realise that when there are about 15 or 20 candidates for something, most of them are there in some respect. i'll not be surprised if dark matter comprises of an lsp, massive neutrinos (we already *know* they're a dark matter, just not how significant they are if at all), relativistic corrections to the naive newtonian models of galaxies (galaxies are not living in flat space, they live in curved space which for spiral galaxies is cylindrical), a misapplication of the friedman equations in cosmology (the issue there being that they describe the universe "on average" and yet we haven't the faintest clue how that "average" is taken), and probably a host of other things i've forgotten and even others that have never been thought of yet.

Re:high enough energy? (5, Informative)

boristhespider (1678416) | more than 3 years ago | (#35349166)

No. We can never smash hard enough to disprove supersymmetry unless we find something that directly contradicts it. To put it another way, if all the LHC finds is a Higg's and expected results from the standard model, it doesn't actually disprove supersymmetry since any model of supersymmetry has so many parameters that you can tweak a few of them and lift the superpartners back up above the LHC's maximum energies. That is *always* going to be possible -- theoretically a limit would be if we had particle accelerators that reached the Planck energy and people would finally be saying "hang on, something's up here; we should be seeing quantum gravity by now and we're still not seeing the quarkinos", but in reality we're never getting to anything like an energy that would rule it out.

What's a lot more likely in my mind is that more physicists will begin to drop supersymmetry and look at something else that may actually have observable effects at "low" energies while otherwise the supersymmetry bandwagon will roll happily on with slightly more tightly-constrained parameters.

The hope is that the LHC not only doesn't see supersymmetry but *does* see something utterly unexpected. That's what I want from it. (Actually I want specifically no Higg's boson, and no supersymmetry.) Something unpredicted would rule out supersymmetry not least because any supersymmetric model that could account for it would be a posteriori -- constructed purely to do that and most likely grossly ugly as a result. By definition something unexpected is not a straight prediction of supersymmetric theories, and any model constructed purely to explain it will be under suspicion.

Before getting onto the next bit, the Higg's is not associated with supersymmetry, it's part of the standard model and doesn't require supersymmetry to exist. The Higg's is the last part of the standard model that is yet to be observed. They're different topics, and the LHC is hoped to shed light on both of them. As far as supersymmetry goes, the LHC was built basically to give us a pointer for where to go beyond the standard model and forms of supersymmetry are currently the most widely-favoured options.

The fear (at least my fear) is that the LHC will find nothing. Squat. No supersymmetry, nothing outwith the standard model -- but from my point of view, that it does find a Higg's. That would appear to add support to the standard model, which is a bit of a pain because the standard model's already broken since we *know* neutrinos have to have mass and fudging the standard model to put them in is pretty contrived.

However, not finding a Higg's at all would be brilliant -- so strictly speaking, the LHC finding *nothing at all* would be good. Because the Higg's should be within its capabilities and if it's not there there'll be a lot of head-scratching going on, and I always prefer things being rethought and reanalysed over mindlessly employing techniques chiefly developed in the 40s with QED and brought to fruition in the 70s with QCD and the electroweak theory.

But, in all fairness, I'm not a particle physicist, I'm a cosmologist.

Re:high enough energy? (1)

geekoid (135745) | more than 3 years ago | (#35349990)

well, if it predicts something, and we show that that something doesn't happen then the theory needs to be change to fit the new data. If it can't be changed, then it's dead.

If I say gravity cause something to fall at a rate dependent on it's mass, and then do tests that show that mass is irrelevant to the rate of fall I have disproved my statement. That I can say either 'gravity' doesn't exist or that it exists but mass is irrelevant to the rate of acceleration during a fall.

true, but... (1)

boristhespider (1678416) | more than 3 years ago | (#35350062)

it's not the theory that needs changing in that case, it's just the parameters in the theory. the theory itself is still fine, you just tweak a few numbers and suddenly it's "oh the lsp is up at 20TeV, sorry guys! you built that 15bn euro machine for nothing!" there's something like 127 free parameters in mssm which gives you a *huge* parameter space to run around in and hide from the experimentalists. play this game and the theory is still "valid". play it long enough and everyone else will give up and go and look for something else - but we might have to see a good few people retire before that happens.

Re:true, but... (0)

Anonymous Coward | more than 3 years ago | (#35350512)

It's really refreshing to hear a cosmologist criticize other physicists for running around and hiding in free parameter space from experimentalists.

Cheers.

Re:high enough energy? (1)

sweetser (148397) | more than 3 years ago | (#35350408)

As a cosmologist, how do you feel about rethought and reanalysis of 1. The particles that cause inflation, 2. Dark matter needed for various galaxies and clusters of galaxies, 3. Dark energy needed for the accelerating universe?

There are problems with the classic big bang model, with velocities seen in galaxies, and the acceleration of the galaxies. My money is that all of these are hard math problems, not a new type of matter. I even have a specific equation I would like to apply to these problems in particular, but I am not good enough at relativistic rocket science to give it a go.

I am with you on the no Higgs/no supersymmetry.
Doug

Re:high enough energy? (1)

kittylyst (1467097) | more than 3 years ago | (#35350602)

"To put it another way, if all the LHC finds is a Higg's and expected results from the standard model, it doesn't actually disprove supersymmetry since any model of supersymmetry has so many parameters that you can tweak a few of them and lift the superpartners back up above the LHC's maximum energies."

Errr, not really. What you said there is pretty much akin to tweaking Newtonian physics by adding small additional terms to produce large-scale structure which matches observations. Or claiming that a geocentric model is fine because, y'know, epicycles can totally cook up anything required to fit observation of the solar system (NB: Please Note: I'm not a gravity bod).

The big problem with a lot of SUSY theories is vacuum stability.

One line of argument goes that something like this: "If there isn't a member of a Higgs n-let below a certain mass, then the vacuum is no longer stable. So by ruling out Higgs at various energies, we rule out certain classes of possible SUSY. As the mass at which we've ruled out Higgs gets higher and higher, the SUSYs which still aren't ruled out get more and more contrived."

At some point (and it's a point which most reasonable people would agree is now not too far off), SUSY stops looking like a like a fundamental law of the Universe and more and more like a hack-job.

Yes, maybe... (0)

Anonymous Coward | more than 3 years ago | (#35349230)

Semi-naive answer: there are conjectures about the properties of the alleged Higgs boson. From these conjectures follow some predictions about the energies that are needed to expose the Higgs boson. The LHC can reach these energy levels, so if all goes well the Higgs will be found.

However, reality often gets in the way of scientific progress. Maybe the conjectures aren't good enough, maybe the Higgs Boson is just outside the reach of LHC, and maybe there is no Higgs boson at all. That's the hard part of doing science, you are operating under assumptions until proven correct. It's what makes science fun and exciting. It's also what makes it such a cruel bitch.

Re:Yes, maybe... (1)

slinches (1540051) | more than 3 years ago | (#35349644)

The way I understand it, the models predict that at a given collision energy level, there will be a certain probability that a Higgs boson can be detected. If a particle accelerator is run at this energy for a certain number of collisions (at lower energies this could take years due to the extremely low probabilities involved) and there is no indication of the Higgs, it means that the model is very unlikely to be valid. Supposedly at the levels the LHC has been operating without finding evidence of the Higgs, a subset of the hypotheses that predict measurable effects at lower energies are less likely now. Apparently, the upcoming two year run will cover a large portion of the current models' predictions and could invalidate them if it's not found. Since the most popular versions of the standard model rely on a measurable Higgs boson, not finding it could mean that we don't understand the universe as well as we think and would need new models that explain how particles have mass without it.

Re:Yes, maybe... (1)

tendrousbeastie (961038) | more than 3 years ago | (#35350194)

From what I understand, there is a huge amount of chance. If you feed an amount of energy into a small point in space where that energy corresponds exactly to the mass of a particle (via e=mc2) then you will get that particle.

If you feed more energy into that area of space you may get that particle, or you may get other combinations of lighter particles whose mass/energy fit within the energy you've fed in.

As I understand it, to find the Higgs particle you'd need to use the correct energy level (i.e. fire a proton through the accelerator with just the right energy, not too low and not too high)

This was certainly the story for the J/ particle, only when they tuned their system to the exact energy (lower than the system was designed for) did they find it properly.

Re:high enough energy? (0)

Anonymous Coward | more than 3 years ago | (#35349522)

There are bounds on the potential mass of the Higgs boson from precision measurements. The LHC with enough time should be able to see the Higgs, if its' mass is within those bounds. If it's not within those bounds, then the Standard Model isn't just incomplete, it's wrong. Considering how well the Standard Model has stood up to every other test, that's pretty unlikely.

In the search for supersymmetry, you can't make such definitive statements. The parameters of supersymmetry can be varied so that supersymmetry shows up at any energy scale from what the LHC can see up to the Planck scale. However, as the energy scale of supersymmetry goes up, supersymmetry solves fewer and fewer problems in particle physics. It no longer is a "natural" solution to the hierarchy problem, the lightest supersymmetric particle can't be a component of dark matter, and so on. Therefore, we'd have to start looking for other solutions to those problems which may or may not be consistent with supersymmetry existing at an energy scale which hasn't been ruled out.

Re:high enough energy? (1)

gwoptics (2006568) | more than 3 years ago | (#35349542)

Yes. No. The LHC might be the last collider to provide enough energy to find something really exciting. But, yes, a no-discovery so far does not mean anything but if in a few years time the LHC has not seen a new particle this would be a significant result. Andreas

Re:high enough energy? (1)

mcelrath (8027) | more than 3 years ago | (#35350420)

Unfortunately physicists stopped looking for falsifiable theories a long time ago. They're bad for your career. They also forgot about Occam's razor. Supersymmetry is not a theory, but a principle, the simplest theory [wikipedia.org] built upon it has 120 new free parameters. That's to be compared with the 19 of the Standard Model [wikipedia.org] . It may solve one or two problems, at the expense of 120 new ones. As a consequence, it is nearly impossible to disprove supersymmetry. (and definitely impossible using only the LHC) One can always push the mass scale of super-partner particles above the energies of the LHC, and the theory lives, though it is now somewhat uglier.

Despite the fact that scientific advancement is always predicated upon reductionism we've created a very large pile of theories, each with a very large number of parameters, that have the same property of being un-falsifiable. This is essentially a consequence of the "publish or perish" nature of modern academic science. A theory with 120 free parameters represents many career's worth of exploring those parameters, in the hopes that one lucky guess and you might win the lottery, and your theory might be real. Hypothesizing a new symmetry, new force, or new particle (with no evidence whatsoever) and exploring its consequences is a game that increases the complexity of the theory, but is a good career path, as it generates an infinite number of papers, but bad for science, since it reduces physicists to monkeys at typewriters, trying to produce the works of Shakespeare. Such brains could be put to better use. We assume we already know the rules of the universe, and we apply them to make new theories. However it is demonstrable that we don't even know the rules. Even with supersymmetry (or any of the other theories), certain calculations give results in contradiction to our observed universe.

Let's contrast that with the way science is supposed to work. Let's try to take those 19 parameters of the Standard Model, and make it 18, or 10, or 1, or 0. For comparison consider the modern theory of Quantum Electrodynamics. We once thought magnetism and the electric force were separate. Feynman, Dirac, and many others built the modern theory, in which they are different aspects of the same force, the coupling constant of which is now one of the most precise measurements in all of science. However making simpler theories is time consuming and error prone, full of blind alleys and fruitless hypotheses that must be navigated. Science does not proceed by "Eureka!" moments in which everything is suddenly clear. It's painstaking work of mapping out what doesn't work, to clear the way for what does. If the path to a better theory were clear, everyone would build a highway to it. To find it, one must enter the wilderness. This is a career killer. Blind alleys are time consuming to navigate, and do not result in publications. During that time your colleagues will look at you strangely and wonder what the hell you're doing with your time. You will soon find yourself without a job.

On a positive note, no matter how degenerate our theories become, experiments like the LHC are our saving grace. They beat us over the head with a blunt instrument, and force us to face reality. In the words of Sherlock Holmes, "It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts" and that is the situation modern theoretical physics is in. We are theorizing without data, and building theories to explain statistical anomalies and backgrounds. The LHC will discover the origin of mass, whether it is the Higgs particle or not (and whether supersymmetry is participating or not). The LHC is far, far more important than all our fancy theories. We should always take data. It is how we learn. The notion that theorists have correctly guessed at the structure of the universe, absent any data, is naive.

-- Disgruntled and angry, unemployed theoretical physicist

High-maintenance apparatus (0)

Anonymous Coward | more than 3 years ago | (#35349024)

"If super particles don't appear by 2012, then physicists might give up on the theory for good."

Why, because they're late? "They should have been here by now. Ten more minutes and we're leaving without them. I'm a young, attractive particle smasher. I don't need this. Higgs is probably waiting for that skank ILC to come on line. "

Or is this shorthand for "If super particles don't appear at the energy levels we expect the LHC to be producing in 2012, physicists might give up on the theory for good."?

Luminosity, not energy levels (1)

pavon (30274) | more than 3 years ago | (#35349170)

The energy levels for LHC will be staying about the same from now till 2012. The difference is that it will be collecting more data, and thus increasing the luminocity [wikipedia.org] and statistical confidence that if supersymmetry is correct we would have seen something. This is the same reason that people were betting on whether Fermilab might find the Higgs Boson before the LHC; not because it is increasing energy levels, but because it has had more time to collect data and thus increase its luminosity. So it really is a matter of waiting until it has been running long enough.

They'll turn it up from 700GeV to 1000GeV (1)

ReedYoung (1282222) | more than 3 years ago | (#35350372)

But colliders have failed to turn up direct evidence of the super particles predicted by the theory. The Tevatron at the Fermi National Accelerator Laboratory in Batavia, Illinois, for example, has found no evidence of supersymmetrical quarks ('squarks') at masses of up to 379 gigaelectronvolts (energy and mass are used interchangeably in the world of particle physics).

The LHC is now rapidly accumulating data at higher energies, ruling out heavier territory for the super particles. This creates a serious problem for SUSY (see 'SUSY's mid-life crisis'). As the super particles increase in mass, they no longer perfectly cancel out the troubling quantum fluctuations that they were meant to correct. Theorists can still make SUSY work, but only by assuming very specific masses for the super particles — the kind of fine-tuning exercise that the theory was invented to avoid. As the LHC collects more data, SUSY will require increasingly intrusive tweaks to the masses of the particles.

So far the LHC has doubled the mass limit set by the Tevatron, showing no evidence of squarks at energies up to about 700gigaelectronvolts. By the end of the year, it will reach 1,000gigaelectronvolts — potentially ruling out some of the most favoured variations of supersymmetry theory.

http://www.nature.com/news/2011/110228/full/471013a.html [nature.com]

So, they are planning on some increase in energy levels between now and 2012. Not an order of magnitude, I know, but 1000 is nearly 50% more than 700, and that's not "about the same" to me. So I think it's a combination of acquiring more data, and slowly increasing the energy levels (to LHC's maximum output, I assume?) until either supersymmetric particles are detected, or we have turned up the energy so much without finding anything that we have to give up on SUSY.

Different meaning. (1)

pavon (30274) | more than 3 years ago | (#35350560)

What they are saying in that paragraph is that enough data has been collected to rule out the possibility of squarks whose energy is 700 TeV or less. By the end of the year enough data will have been collected to rule out 1 TeV squarks. However, the total energy of the collider will be 7 TeV for the entire duration [web.cern.ch] (two 3.5 TeV beams hitting head-on). This is the same energy level [web.cern.ch] that was met before it shut down for the winter break.

No Higgs, no super symmetry, but a t-shirt (2)

sweetser (148397) | more than 3 years ago | (#35349188)

That's my prediction, and my t-shirt: http://bit.ly/GEMtshirt [bit.ly]

The idea: Maxwell's field theory is the best one we have, the basis of the standard model by swapping out the gauge groups. I figured out how to write the Lagrange density (every way energy can be exchanged inside a box) using quaternions. That is not so hard. Do you know how to factor (B^2 - E^2)? If so, then (Del A - (Del A)*)(A Del - (A Del)*) is the same thing, quaternion style. The quaternions cannot do gravity which involves totally symmetric changes in a metric. Therefore I used an even less popular algebra known by names such as the hypercomplex numbers or the Klein 4-group. Put that into the Lagrangian, which flips exactly half the signs. That makes my proposal for gravity.

Combine the EM quaternion rewrite with the hypercomplex gravity Lagrangian, but without that -(Del A)* thing which was subtracting away the gauge term. The gauge term is there in both the gravity and EM portion, but they wipe out each other, so gravity and EM apply to massive particles, but overall the Lagrangian is gauge invariant. The Higgs mechanism works via a clever solution. My unified standard model works via a clever Lagragian.

By the end of 2012, I will know if my t-shirt is wrong because the Higgs and/or supersymmetric particles are found, or my t-shirt is barking near the right tree.
Doug

Supporting material about the t-shirt
http://bit.ly/GEMIAPday1video
http://bit.ly/GEMIAPday1pdf

Re:No Higgs, no super symmetry, but a t-shirt (1)

pavon (30274) | more than 3 years ago | (#35349272)

This stuff is way above my head, but I was wondering why the legend for the T-Shirt included × for quaternion multiplication, but × doesn't show up in the equation.

Re:No Higgs, no super symmetry, but a t-shirt (1)

sweetser (148397) | more than 3 years ago | (#35349394)

A fine question. x is the "implied" multiplication. In C programming, you have to write A * B. In physics books, you write A B. So any implied multiplication uses quaternions, any box-times is hypercomplex.

The video is geared towards people who can do 1st year college calculus, or high school level if you are headed off to MIT.

Re:No Higgs, no super symmetry, but a t-shirt (0)

Anonymous Coward | more than 3 years ago | (#35349548)

Followed your link; I give up -- what is the "secrete" trick?

Re:No Higgs, no super symmetry, but a t-shirt (1)

sweetser (148397) | more than 3 years ago | (#35349716)

Gravity is literally a universal love force: no matter what you are made of, everything else in the Universe wants to get closer to you (whether you have showed or not). We all want to rush to the center of the Earth - a fall that would take a little over 20 minutes - but are stuck in an atomic-level traffic jam. How can we make universal attraction a law? My proposal is that the rule for multiplying 4 numbers together does not have a single minus sign. Without a minus sign, repelling does not happen. That is the accounting secret. The all-positive product is the box-times symbols on the t-shirt, or hypercomplex numbers/Klein 4-group on wikipedia. Physicists use something known as tensor calculus, and that blocks a direct road to this kind of multiplication.

Re:No Higgs, no super symmetry, but a t-shirt (1)

maxwell demon (590494) | more than 3 years ago | (#35349904)

I just noted the t-shirt contains the word "Tolkien" ... maybe you better hide it from Tolkien Estate.

Re:No Higgs, no super symmetry, but a t-shirt (1)

sweetser (148397) | more than 3 years ago | (#35350024)

A legit concern, but J. R. R. Albert Tolkien was Jewish, more by tradition than some sort of ultra-conservative flavor, and not born a Roman Catholic.

Re:No Higgs, no super symmetry, but a t-shirt (1)

maxwell demon (590494) | more than 3 years ago | (#35349942)

BTW, I noted that your page contains links to bit.ly -- I can understand that on a forum (although I'd prefer preview.tinyurl.com), but for a web page? Are you trying to hide something?

Re:No Higgs, no super symmetry, but a t-shirt (1)

sweetser (148397) | more than 3 years ago | (#35349988)

Nope. I can remember the custom bit.ly strings, but not YouTube strings. There may be better ways, but for now it is the way I know how to do it.

Re:No Higgs, no super symmetry, but a t-shirt (1)

Dachannien (617929) | more than 3 years ago | (#35350572)

You could always follow the bit.ly URLs yourself and then post the YouTube URL that results.

That's what's wrong with Physics today (1, Insightful)

gr8_phk (621180) | more than 3 years ago | (#35349248)

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 (1)

BJ_Covert_Action (1499847) | more than 3 years ago | (#35349358)

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.

Isn't that kind of, you know, what drives science forward? Questioning the accepted laws as they are and seeking ways to expand upon them, generalize them, or all around uproot them to explain some currently inexplicable observation we've made?

Re:That's what's wrong with Physics today (1)

marcosdumay (620877) | more than 3 years ago | (#35349586)

Hum? Kepler's laws do not apply to galaxies. Everybody knows that, and that's why people came out with dark matter. Also, altough the mass distribution of an spiral galaxy isn't very similar to a point mass, eliptical ones are quite well approximated by a point.

Re:That's what's wrong with Physics today (3, Insightful)

Mr_Huber (160160) | more than 3 years ago | (#35349676)

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:That's what's wrong with Physics today (0)

Anonymous Coward | more than 3 years ago | (#35349854)

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.

Quoting just because it's awesome. I think this is a wonderful summary.

Re:That's what's wrong with Physics today (1)

mangu (126918) | more than 3 years ago | (#35349938)

Dark matter is real and we now have tools with which we can spot it

Or not. The Bullet cluster is one example that confirms some predictions of dark matter, but there still remain other problems, like the cuspy halo problem [wikipedia.org] .

Reality simply does not diverge from the theories unless we get into some really exotic conditions

And that should get worse as our theories become more precise.

The problem with general relativity is that it gives very precise predictions for orbits in our solar system, but we do not have good measurements for bigger orbits. The Pioneer anomaly [wikipedia.org] and the flyby anomaly [wikipedia.org] could be indications of a deviation from general relativity. Perhaps a future theory of gravitation could explain both the Pioneer anomaly and galaxy rotation without the need for dark matter. However to test if the Pioneer anomaly really exists one would need to perform new, more precise, measurements which would be very expensive and take years.

The problem with ground breaking theories is that they create the need to rewrite large portions of current physics and that takes time and effort, so scientists usually are reluctant to accept them. That's what happened with special relativity, only when several different versions of the Michelson-Morley experiment seemed to prove in an incontrovertible way that aether drift did not exist scientists started looking for alternative theories. The main problem today is that experiments to detect limitations in general relativity are much more difficult to perform than the experiments they did a hundred or more years ago to prove the inexistence of aether drift.

Warning: Off-Topic Rant WIthin (1)

boristhespider (1678416) | more than 3 years ago | (#35349984)

"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."

Not having a beef with you at all because I agree with basically everything you say, but this is the bit that really upsets me about dark matter studies. (Not you -- about dark matter in general :) ) There is almost certainly no *single cause* of what we call "dark matter" (which is, after all, just the observation of anomalous rotation curves. Ignore cosmological dark matter -- in principle that's totally unconnected and is just a term appearing in the Friedman equations which are totally phenomenological). We know that MACHOs exist. We also know that they're nothing like populous enough to be "the" dark matter. But we ignore them from then on, mainly because it makes our lives easier if we pretend they don't exist. But they do. We know neutrinos have mass. We also know that they're not massive enough to be "the" dark matter, but dark matter they certainly are. Warm, likely to dissipate from galaxies, but dark matter nonetheless. But we ignore them, too. We know an LSP is a dark matter, so for some reason we assume it HAS to exist and even attribute anomalous signals from the centre of the galaxy to dark matter annihilations and invent new channels for LSPs to interact and decay. But, for the sake of argument, let's say an LSP exists. Then it's a dark matter. And particle physicists will say it's "the" dark matter -- but it's not and it's entirely possible that actually it will only be the most significant component, the same as assuming the universe is hydrogen is a good first approximation and an appallingly shonky second approximation.

Add to that that it's undeniable that (spiral) galaxies rotate in a cylindrical metric and that just because the Newtonian potential is small doesn't change the fundamental nature of a spacetime, and it's at least suggestive. There are other papers out there that have looked at this and they've been better done and concluded that it can't be dark matter but it reduces the need by maybe 10% or 20%, in spiral galaxies. Add in a more complicated geometry to model the central bulge and maybe that'll go up to 25%. That's 10%, conservatively speaking, of a problem we're all masturbating over supersymmetry to solve potentially gone using century-old GR. Maybe an LSP is 90% of the dark matter, but it wouldn't be the whole thing. (Or maybe actually model it properly and relativistic effects *don't* alter the rotationc urves significantly. That's also cool.)

Then of course there's MOND. Is MOND fundamental? Nope, nothing like, it's pure phenomenology. But it fits galaxies way too close for comfort. You can ignore that all you like, but it's suggestive of at least some underlying correlation, if not actually modified gravity. The fact that it falls apart dramatically in clusters seems to argue against it being fundamental, but something fishy is going on.

As for the bullet cluster, even TeVeS (basically a relativistic generalisation of MOND) can fit that... if you play around and add in some massive neutrinos with a suspiciously high mass. Lower that mass and there's still a missing mass problem, but I'm happy with an LSP filling that if necessary -- but the case isn't really clear cut for dark matter having to be particle-like.

And it's certainly not clear cut for there being "a" dark matter. The way I see it it's actually clear-cut that there are various things going on, from new physics to a poor use of the old stuff, to supersymmetric particles, to actually just all the old stuff being there anyway as MACHOs and neutrinos.

Rant over. :)

Re:That's what's wrong with Physics today (1)

LordNacho (1909280) | more than 3 years ago | (#35350044)

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.

Well hey, there's still physical phenomena which are poorly understood. OTTOMH, sonoluminescence, turbulence.

Here's some more: http://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics [wikipedia.org]

Re:That's what's wrong with Physics today (0)

Anonymous Coward | more than 3 years ago | (#35350168)

You are what is wrong with physics, you are your kind.
You people who stick to "the things they know best" and fear change, fear going out looking for new things.
People like you are the cancer of science in general.

Also, why don't you go wake them all up.
Why don't you push for it?
Where are your proofs for the universe without dark matter?
Never mind even dark energy, you explained that one too?

...only until... (1)

cdpage (1172729) | more than 3 years ago | (#35349262)

They may give up on this theory, but only until they build a bigger collider.

Re:...only until... (1)

slick7 (1703596) | more than 3 years ago | (#35349426)

Given enough power and time, they will eventually break something.
Werner von Braun said; "Research is what you're doing when you don't know what you're doing".

Dark Matter (1)

Maritz (1829006) | more than 3 years ago | (#35349306)

It would be exciting if superpartners to the current particle zoo were found, as it would give us a real neat and tidy explanation for dark matter, the neutralino [wikipedia.org] being an example of a good candidate dark matter particle. Personally I think it'd be cooler than finding the Higgs but I guess we'll know once the data comes in.

too many tenures on the line (0)

Anonymous Coward | more than 3 years ago | (#35349398)

Supersymmetry won't die, there are too many tenured faculty in that community. At least it won't happen until someone finds a different reason for mass generation.

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