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String Theory Put to the Test
secretsather writes to mention that scientists have come up with a definitive test that could prove or disprove string theory. The project is described as "Similar to the well known U.S. particle collider at Fermi Lab, the Large Hadron Collider, scheduled for November 2007, is expected to be the largest, and highest energy particle accelerator in existence; it will use liquid helium cooled superconducting magnets to produce electric fields that will propel particles to near light speeds in a 16.7 mile circular tunnel. They then introduce a new particle into the accelerator, which collides with the existing ones, scattering many other mysterious subatomic particles about."
Welcome to slashdot; here's your junk science for the day.
You can't prove string theory through experimentation, all you can do is attempt to disprove it.
Liberty you never use is liberty you lose.
It can't prove string theory. It can *support* it, or it can disprove it, falsify it, contradict it. But it can't confirm it. All the experimental data in the universe can't do that.
42.
Did anyone honestly think that the answer would be different?
'Loose' is when your pants are three sizes too big. 'Lose' is when you misuse 'loose'.
http://www.xkcd.com/c171.html
-- Too lazy to get a lower UID.
I say, kill all the particles and let science sort 'em out...
I hope, when they die, cartoon characters have to answer for their sins.
Oh...Large Hadron Collider. If it was in the Castro district I would really be suspicious.
I'm by no means an expert in string theory. I barely grasp the basic concepts. However I am an engineer who has taken a LOT of physics classes over the years and I'm not completely ignorant either.
String theory has always struck me as a modern day version of epicycles before it was realized that planets follow ellipses instead of circles. It just seems like we're trying to fit the math to the model instead of modifying the model so that the math makes sense. Add in the fact that it makes no testable predictions (not yet anyway) and it's bordering on not being science anymore. Maybe technology advances will change that but then again maybe not.
Maybe string theory is right, I don't honestly know. But it seems like a lot of group think is going on and little progress is being made.
I think it's funny how the article forgets to mention that the LH collider is located at the CERN (the European nuclear physics institute). As a matter of fact, it is not only in Switzerland, but extends to France as well. The article only mentions it is similar to the U.S. Fermilab accelerator, but then forgets to add that there are many kinds of accelerators world wide.
Funny, ain't it?
The number of dimensions isn't that high. When all of the string theories are combined into M-theory, the total number of dimensions is eleven, IIRC. Harder to understand? Yes. Impossible to visualize? Yep. But not abhorrently high.
You can never go home again... but I guess you can shop there.
It thought this was cleared up years ago:
Scanning/Copying based on a terminator byte pattern is fraught with error and is definitely not secure.
Buffer sizes are terribly problematic when left tot he caller to check on overflow. It must be in the methods, and thus part of the data structure. (see point above).
Strings these days are UTF-7 or 8, which makes them an even better candidate for a object-based construct rather than a memory map.
I'd like to point out the....oh, wait...
Nigel: As you can see, our theories all go to eleven, right across the board. Look: eleven, eleven, eleven.
Marty: Does that mean it's better? Is it any better?
Nigel, well, it's one more, isn't it? Most blokes, their theories only use ten dimensions. They're at ten, where do they have to go from there? When we need that extra push over the cliff, you know what we do?
Marty: Put it up to eleven?
Nigel: Eleven. Exactly. One more!
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
Not at all. You merely have to project one of the dimensions down so that you're only considering a 10-dimensional space.
Ben Hocking
Need a professional organizer?
I don't think it's whining. The public's confusion about science surely stems in part from sloppy reporting.
How often have we heard someone claim that we shouldn't allow something because it has never been proven to be safe? Such comments show serious misunderstanding about the nature of knowledge.
From the wording in the article it sounds like they actually want string theory to fail. . .
.despite the fact that we have few alternatives so far.
A test in which a theory fails is the most useful sort of test.
. .
I cannot accept a theory simply because I don't know what to replace it with. Make the tests, generate failures; and then new theories which take the failures into account. That's how the alternatives come into being in the first place. That's why the "failures" are the most useful.
"Successes" only make us complacent with the state of our knowledge, which might well be wrong anyway. "Failures" let us know where we lack knowledge. Science is not done where we know, but where "here there be dragons." It's about exploring the dark corners of the map, not sitting in our offices diddling with ourselves.
We leave that sort of thing to the engineers.
And think about this:
Who says we need an alternative? The quest for a Unified Field Theory is an asthetic desire on the part of physicists. The universe is well known for taking our asthetic desires and shoving them up our collective arses.
Perhaps there can be only two.
KFG
It's been known since the 1920s that adding extra spacetime dimensions allows you to unify forces; Kaluza and Klein successfully unified classical electromagnetism and gravity that way, with a theory in 5 spacetime dimensions. Unfortunately, this idea can't be readily extended to all the forces in the Standard Model, and the unified theory is at least as difficult to quantize as gravity alone.
From a different perspective, leaving gravity out of it, there are the grand unified theories. They too have "extra dimensions", except that the extra dimensions are not of spacetime, but of an internal "gauge" symmetry space. (Kaluza-Klein theory basically turns these internal gauge dimensions into true space dimensions, paving the way to a gravitational theory.)
String theory also does not add as many "undefinable, physically meaningless constants as possible". Indeed, it has fewer constants than the Standard Model. In fact, it has only one constant, which is certaintly definable: it is the string tension. Furthermore, the dynamics of string theory are unique, unlike the quantum field theories. (You can write down infinitely many different particle physics theories with different particle content and interactions, but all of the string theories are part of the same theory, and all the strings obey the same fundamental laws of interaction.)
In short, string theory is not a totally contrived fudge; pretty much all of the ideas that led to semi-successful unified field theories found their way into string theory in a natural and uniquely determined way.
The energies that will be created in the LHC happen on a daily basis in our upper atmosphere. The only difference is that we will have detectors in the immediate vicinity.
Ben Hocking
Need a professional organizer?
And furthermore, now that I have read the "article", it turns out to be a freaking BLOG POST containing nine whole sentences. NINE! Sheesh. Secretsather, you deserve some serious downmods for your laziness and obvious lack of subject knowledge.
A quick news search reveals much more informative articles, which allows one to find the original journal article. Here's the abstract...
...most of which is beyond grasp of what I remember from 200-level college physics. Would a domain expert care to jump in now?
String theory has one particle - the string. It has one force which emerges from the very simple dynamics put into it at the outset. A wide spectrum of particles and interactions emerges from it in a natural way. There is little choice for the dimension of spacetime - the theory locks it down from the beginning. Gravity emerges from it naturally - something that doesn't even get mentioned in the standard model. There are close to zero arbitrary constants. And at bottom, the initial assumptions of String Theory are really simple. Simpler than other quantum field theories.
The problem with String Theory is that taken at surface value it doesn't match the universe we see. We don't see a 10-dimensional universe, we don't see the predicted spectrum of particles and so on. The publicised problems we see with String theory are from all the attempts to make our 4D universe emerge from it - and the incredible freedom we have in doing so (eg. by folding up dimensions in various ways). At core, String theory is simple, beautiful and as far from arbitrary as you can imagine. There are all kinds of things wrong with String theory. But they have nothing to do with "adding as many dimensions and undefinable, physically meaningless constants as possible", which sounds more like the ramblings of someone who doesn't have a clue what String Theory is about.
Note that I am neither for nor against String Theory, which makes me part of a tiny minority in the physics world. I certainly doubt it's the ultimate theory of anything, but I also think that there is a lot of uninformed criticism of it. I'm just telling it like it is without my own ax to grind.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
it will use liquid helium cooled superconducting magnets to produce electric fields that will propel particles to near light speeds in a 16.7 mile circular tunnel. They then introduce a new particle into the accelerator, which collides with the existing ones, scattering many other mysterious subatomic particles about.
This is why the Mythbusters should not be allowed to design scientific equipment. I can picture Adam dancing about in girlish glee even now...
If I knew the wedgies I gave you back in 6th grade would have resulted in this . . . I might have taken a moments pause.
Thou shalt have four dimensions. No more, no less. Four shall be the number of thy dimensions, and the number of the dimensions shall be four. Five shalt thou not have, neither thou have three, excepting that thou then proceed to four. Six is right out.
Unfortunately, that site is totally bogus. Interesting, but it's entirely unrelated to string theory, which the author seems to mention just to lend his ideas some credibility.
THE EARTH REVOLVES AROUND THE SUN?? You must be joking. I can clearly see the sun rising and setting. Any theory that interferes with the perceptions that I am comfortable with, is obviously bollocks. Last time I checked I couldn't see any evidence for the earth revolving around the sun, even when looking under the sofa.
Censorship is telling a man he can't have a steak just because a baby can't chew it. --Mark Twain
As I always like to point out, the most important thing to remember about Occam's Razor is that it's a rule of thumb, not a Law of Nature. If two proposed theories otherwise seem to work similarly well, but one introduces fewer assumptions than the other, Occam's Razor suggests that the former is probably better than the latter, but you can't take this as "proof" -- at best, it lets you make a better educated guess about which avenue is likely to be more fruitful to continue exploring.
David Gould
main(i){putchar(340056100>>(i-1)*5&31|!!(i<6)<< 6)&&main(++i);}