Exploring Superstrings in the Lab 312
ultracool writes "Physicists at Utrecht University in the Netherlands have come up with a way of observing a superstring by utilizing Bose-Einstein condensation (BEC). A one-dimensional BEC in an optical lattice is rapidly rotated, causing a quantized vortex to form. The bosonic part of the superstring consists of this vortex line. Inside the vortex, they would trap an ultracold cloud of fermionic atoms. Hopefully this will allow observation of the supersymmetry between bosons and fermions, thus providing the first experimental evidence to support superstring theory."
Woah.. (Score:5, Funny)
Re:Woah.. (Score:2, Funny)
"Pro-actively enabling the supersymmetry between bosons and fermions..."
Comment removed (Score:5, Funny)
Re:Woah.. (Score:4, Funny)
Re:Woah.. (Score:3, Funny)
Re:Woah.. (Score:3, Informative)
These books went a long way towards helping... (Score:2, Informative)
Though I haven't compleated it yet I'll got "The Elegant Universe. Richard Morris [amazon.com] also wrote some good books before he died.
FalconRe:Woah.. (Score:2)
Re:Woah.. (Score:4, Funny)
Of course it would.
Re:Woah.. (Score:2, Funny)
Re:Woah.. (Score:4, Funny)
Re:Woah.. (Score:2)
I use super-strings all the time (Score:5, Funny)
They're great. You can modify them and they aren't synchronized so they're fast, too. If these scientists are only just now discovering them they should try reading some newsgroups.
Re:I use super-strings all the time (Score:2)
But then again -- it's Slashdot.
More info... (Score:5, Informative)
Beneath all of the optimism... (Score:2)
No Way! (Score:3, Funny)
Yes it is. (Score:2, Funny)
Of course it's possible to see symmetry between bosoms and females--
(hears enraged Slashdotters worldwide screaming bosons and fermions)
--what? nah, I've no idea about those.
I saw that episode (Score:3, Funny)
It might not hurt... (Score:5, Informative)
BEC wikipedia page [wikipedia.org]
BEC home page at Colorado [colorado.edu]
BEC at NIST [nist.gov]
What is a BEC? [physlink.com]
Re:It might not hurt... (Score:3, Funny)
I want a room temp condensate (Score:2)
Just pop open the bottle and show friends how the BEC flows up the wall.. down the bottle, over your arm and onto the floor..
I thought liquid helium was the best way to learn about BECs
Re:I want a room temp condensate (Score:2)
Re:I want a room temp condensate (Score:4, Funny)
If you can flow liquid helium up your arm at room temperature, it's time to talk to your landlord ASAP.
Re:I want a room temp condensate (Score:2, Informative)
The poster is probably just mistaking the instantly condensed nitrogen from the atmosphere for liquid helium. Liquid nitrogen (and oxygen the other gases in our atmosphere) runs down the plumbing of your helium container as the liquid boils off and escapes.
Having LN2 run down your arm is not very pleasant either, however. Stings like electric shock at first, and if it stops stinging you know you're in
And here's what they'll see... (Score:2)
Re:And here's what they'll see... (Score:2, Funny)
Supersymmetry != string theory (Score:5, Insightful)
Any string theorists out there want to chime in?
Re:Supersymmetry != string theory (Score:5, Informative)
but IANAST.
Re:Supersymmetry != string theory (Score:4, Informative)
The point is that, unless my memory of the order of progress is wrong, super-symmetry is relatively new to string-theory and definitely wasn't part of the original models. I do not know that disproving super-symmetry disproves all branches of string-theory. No branch yet has experimental prudence, so it's still possible that after back-tracking, one of the earlier branches was on the right track.
Not just wishful thinking, I'm demonstrating that the disproof of super-symmetry does not end string theory; just string theory as we (read me) know it.
Re:Supersymmetry != string theory (Score:2)
Re:Supersymmetry != string theory (Score:4, Informative)
Nothing can prove string theory. You can only show that the observed behavior of something is consistent with string theory.
But, from what you say, it sounds like there are a number of competing theories which all predict a certain kind of supersymmetric behavior for fermions and bosons.
So, if this experiment works as string theory predicts, string theory and a number of other theories that predict the same thing get a feather in their collective caps.
Re:Supersymmetry != string theory (Score:2)
Re:Supersymmetry != string theory (Score:2)
just like quantum field theory is the set of axioms from quantum mechanics plus the poincare group.
Re:Supersymmetry != string theory (Score:2)
I grant this is true. All you need for an axiom mandating the existence of a supersymmetry is the presence of a superalgebra perhaps with a little additional structure. OTOH (and IMHO), it's likely that supersymmetry will be described through a more parsimonious axiom
Re:Supersymmetry != string theory (Score:2)
I completely agree. There currently isn't a set of
Re:Supersymmetry != string theory (Score:2)
Re:Supersymmetry != string theory (Score:5, Insightful)
Dude, proof only exists within closed formal systems. The universe does not come with an end-user-license promising that any observation *ever* can be repeated, e.g. that the sun comes up tomorrow, or that protons don't decay into Mars Bars.
What we've learned about the universe is that physical observation is highly (some say unrealistically) compressible. We write down a small set of rules (quantum electrodynamics is the best example) and then we find that trillions of physical measurements taken from just about any situation we can think up are *consistent* with the small set of rules we've written down. This doesn't mean the set of rules we've written down it the smallest set of rules consistent with the universe. With each "unification" (e.g. electricity with magnetism) the set of rules becomes more compact relative to how much of the universe it consistently describes. It's important to note that we usually know ahead of time that our system of rules can't possibly be consistent with everything (general relatively and quantum mechanics are inconsistent in their present forms). From the point of view of proof, we knew from the outset that both of these theories are false. Yet each of these theories describes an incredible range of phenomena, and for the most part, the two theories don't much overlap in what they describe. If they did overlap more, it would be far easier to concoct experiments to resolve the known inconsistencies.
I'm quite depressed at how few people are familiar with the work of Kolmogorov and Chaitin. Most physicists fail to fully appreciate these results. The bottom line is that algorithmic compressibility is all we've got, and truth itself is a gossamer filigree we can at best approximate.
Re:Supersymmetry != string theory (Score:4, Insightful)
Re:Supersymmetry != string theory (Score:5, Informative)
MOD PARENT UP! (Score:5, Interesting)
To use a computational analogy, they are simulating the equations of string theory using a BEC as the computer. So whatever results they get had better agree with string theory! They aren't actually testing whether these explain the world, just exploring the equations of string theory with an efficient computer -- the BEC.
Re:MOD PARENT UP! (Score:2)
Whilst what they're doing is very cool, I think the subject is only interesting to the mainstream (as opposed to the trade journals, where this
You're a physicist? Great! (Score:2)
Re:Supersymmetry != string theory (Score:2)
Re:Supersymmetry != string theory (Score:2)
Re:Supersymmetry != string theory (Score:2)
Re:Supersymmetry != string theory (Score:2)
Doubt it's easy, doubt that it's anything we might do in the next 100,000 years. But I also doubt it's impossible.
Which is really besides the point, when you think about it. FTL was an irrelevant detail. It's not necessarily a quality of QE information transfer.
Richards! Behold Doom's UltraGammatronic Ray! (Score:2)
I've been a science geek my whole life, and I have barely an idea of what they are talking about. I thought there was some disagreement about the existence of the multidimensional strings. Is that over now?
We're going to wake up one day and someone in Portugal will have a wormhole operating in his lab, or an antimatter explosion will accidently be set off in Japan. Careful, boys, we're getting into comic book
You call yourself a science geek? (Score:2)
Yes, the high energy physics jargon is terrible and inviting ridicule such as yours. But, remember the Top, Bottom, Charm, Strange, or even the Big bang theory?
The article is terribly written, but it has a link to the original arxiv scientific article. So you are welcomed to go try to understand it.
Btw, this statement by you
I thought there was some disagreement about the existence of the multidimensional
Re:Richards! Behold Doom's UltraGammatronic Ray! (Score:2)
As long as I get superpowers out of the deal, that's cool. Then I'll make the unscrupulous bastards who gave me superpowers pay and pay and pay. Oh yeah, and I'll dominate the world while I'm at it.
Re:Richards! Behold Doom's UltraGammatronic Ray! (Score:2)
If this test doesn't work as predicted then we go "eww, that colour won't go with my hair" and walk away from the shop. This translates to "oh shit, we really don't have a clue what's
Think of the applications! (Score:5, Funny)
This has direct implications for the food industry. No longer will superstring cheese have to be refrigerated, the fermionic atoms will maintain an ultracold cloud around the superstring cheese, keeping it tasty and fresh. Yum.
Don't believe in superstrings ... (Score:2)
I hope they dont "believe" in it either.... yet (Score:4, Insightful)
That beleive stuff is for tooth fairies and god(s)
Proving Superstring Theory would be useful . . (Score:3, Interesting)
What does that mean for us? Well, when Newton found physical laws that worked more generally than Aristotle thought, Physics was born and we were launched into a new era of science. Einstein's Special (and then, afterward) General Relativity made what we consider the modern era possible.
Quantum Physics and Relativity have always been at odds, though. After all, what makes gravity operate at a quantum level? Superstring theory is one of several "theories of everything" that would allow us to explain the world in more general terms--and in the past, every time that has happened, society and technology has taken leaps and bounds forward.
What will happen if we find out that Superstring theory really is the theory of everything? It's liable to be as outlandishly unthought of as space travel to the people of the turn of the 20th century.
Roll 'em (Score:2)
Re:Roll 'em (Score:2)
Far Stringtopia (Score:3, Interesting)
Re:Far Stringtopia (Score:2)
Re:Far Stringtopia (Score:3, Informative)
Re:Far Stringtopia (Score:2)
OTOH, I not a physicist either. Hell, I'm not even sure I spelled it ri
char array (Score:2, Funny)
Give me a break... (Score:2, Interesting)
The scientists are creating a system here that looks quite similar to superstring theory in some ways from a mathematical point of view. They have no way of observing "real" superstrings at these energies. While certainly interesting in its own right, this experiment can in no way provide experimental evidence that superstring theory really de
Superstring? (Score:2, Funny)
Add a smidgen of force.... (Score:2)
Uh huh (Score:2, Funny)
Pfft. Well, obviously.
Ahh.. (Score:3, Funny)
Aha! (Score:2)
Re:Aha! (Score:2)
Re:Aha! (Score:2)
Re:Ahh.. (Score:2)
That was my same thought; given his sense of humor, God just *has* to be an Irishman
Cheers!
SB
(Hey, "he" created bagpipes, incredible music that many loath. Heh)
Well, that's good (Score:2)
Really? (Score:2)
Ummm... Reality check. (Score:5, Informative)
So this is very cool (literally!) science, but NOT a test of superstring theory as a way to describe fundamental particles or interactions. At best, it will provide some interesting checks of the mathematical predictions of string-like theories, but only translated into this system. You still won't know if string theory has any hope of describing real electrons, photons, gravitons, etc.
Re:Ummm... Reality check. (Score:2)
NOT *really* superstrings *or* supersymmetry! (Score:5, Insightful)
The system that these folks propose to study (quantized vorticity in a Bose-Einstein condensate) can be described with the same type of mathematics that is used in superstring theory. The proposed experiments would test the validity of the math. These experiments would say nothing about whether the math of superstring theory is a valid description of the world!
A similar situation would be the following: observing a weight on a spring would confirm the math behind simple harmonic oscillators. It would not, however, tell me anything about whether the vibrational modes of the sun obey those same equations.
Analogy != equivalence!
So in other words? (Score:2)
If this experiment works, it will not prove superstring theory. But if the experiment DOESN'T work, it will DISPROVE or seriously hamper superstring theory?
Re:So in other words? (Score:2)
A physicist? Great! (Score:2)
Ack! (Score:2)
Superstring or M-theory? (Score:2)
As some of you know, there are five superstring [wikipedia.org] theories - M-theory was supposed to "unite" these theories, so to speak. The difference between these superstring theories, is in how the implement supersymmetry, so I guess that this experiment, would somehow point us to which of the five theories are
I am in way over my head here, but perhaps someone is more knowledgable here
...thus providing... (Score:2)
Or not.
I'm afraid... (Score:2)
a layman view on a Boson (Score:2)
Ok this is cool shit. This means that bosons fall throught the table. Literally. Do not put a boson in your pocket, you will loose it! The practical uses for it are stunning! Keys your are garanteed to loose!
whozawhatsa? (Score:2)
precisely! after all, A gleekzorp without a tornpee is like a quop without a fertsneet (sort of).
Re:Why was this posted? (Score:4, Informative)
Re: Why was this posted? (Score:2, Insightful)
Frankly, I'm a little bit annoyed by the treatment of scientific theories as 'absolute truths'. It's been a while since I studied physics, but basically, it works as follows:
You have empirical evidence: things you can feel, touch, hear, smell, see, etc. Beyond that, you have NOTHING. To be more precise: speculation (theory). The best theories are simply the ones that best, or most easily explain empirical fi
Re: Why was this posted? (Score:2)
Sure you can.
Lick your fingers, then with the same hand grab a fork and stick it in the nearest electrical socket. You'll be feeling all sorts of sub-atomic particles.
But seriously, you don't consider bubble chamber photos [web.cern.ch] or electron microscope photos of atoms as conclusive enough, albeit vicarious, touching of atoms and sub-atomic particles to dispense with some of the caveating about atomic theory?
Re: Why was this posted? (Score:3, Informative)
Incorrect! He'll feel electromagnetic fields coursing through his body. This is a valuable experience of one of the four fundamental forces of the universe (jumping out of a fifth story building would give exposure to gravity and technically the strong force though breaking your knuckles with a visegrip is a better demonstration of that force) so it's all to the good. The actual transfer of subatomic particles will be negligiable though. A better choic
Re: Why was this posted? (Score:3, Insightful)
Are you forgetting wave-particle duality? The electromagnetic force is transmitted by electrons, which are subatomic particles. Along with gluons and photons they are bosons, IIRC.
Re:Why was this posted? (Score:2, Informative)
from the article : String theorists attempt to explain all the fundamental particles as vibrations on tiny strings on length scales of about 10-33 metres. The theory naturally includes "supersymmetry" - a symmetry that connects particles with integer spin, known as bosons, to particles with half-integer spin, which are known as fermions. The particles that carry the fundamental forces of nature, such as the photon and the gluon, a
Here's the Nova Special - watch it online (Score:4, Informative)
All 3 hours of it are avaliable on PBS's website.
It's amazing stuff.
The book "The Elegant Universe" by Brain Greene is what the TV Special above is based on.
Definitly worth a look at - if you enjoy the TV special, have a look around for the book... It goes into a LOT more detail.
Re:Here's the Nova Special - watch it online (Score:3, Informative)
Hour 1: 1 [akamai.net], 2 [akamai.net], 3 [akamai.net] 4 [akamai.net], 5 [akamai.net], 6 [akamai.net], 7 [akamai.net], 8 [akamai.net].
Hour 2: 1 [akamai.net], 2 [akamai.net], 3 [akamai.net], 4 [akamai.net], 5 [akamai.net], 6 [akamai.net], 7 [akamai.net], 8 [akamai.net].
Hour 3: 1 [akamai.net], 2 [akamai.net], 3 [akamai.net], 4 [akamai.net], 5 [akamai.net], 6 [akamai.net], 7 [akamai.net], 8 [akamai.net].
I didn't test every one but hopefully you get the idea. You do miss out on some text that is displayed in the popup window that isn't in the actual movie file, such as people's names.
Re:I suppose it makes sense to physicists (Score:5, Informative)
Now, for the reason: if you know some quantum physics, think of taking two composite objects and interchanging them; fermions wavefunctions change sign under this interchange. For the composite object, its wavefunction looks like (an anti-symmetrized) product of single-particle wavefunctions. If those are fermionic and there are an odd number of them in the composite wave function, interchanging the two composite wavefunctions will produce an odd number of sign changes in the product, for an overlal sign change. If there are instead an even number of fermionic single-particle wavefunctions in the composite wavefunction, the resulting even number of sign changes under interchange produces no net sign change in the many-body wavefunction.
This is easily extended to composite objects that are a composite of both bosons and fermions.
Re:I suppose it makes sense to physicists (Score:5, Informative)
So what's the definition of a fermion or a boson, and in this specific case, of a fermionic or bosonic nucleus?
Bosons have integer spin, and fermions have half-integer (n+1/2, where n is a nonnegative integer) spin. The spins of the individual quarks in nucleons (protons and neutrons) always add up to a half-integer, so nucleons are fermions. The quarks themselves are too. The spins of the nucleons in a nucleus can add up in different ways, depending on the number of each kind (proton and neutron) present. When the spins add to become an integer, the nucleus is bosonic. When the spins add to a half-integer, the nucleus is fermionic.
If a given nucleus is fermionic, then identical nuclei of that type obey the Pauli exclusion principle. If the nucleus is bosonic, then the Pauli exclusion principle does not apply to it, and the possibility of a collection of that kind of nucleus forming a BEC exists.
Re:I suppose it makes sense to physicists (Score:2, Interesting)
I bring this up because it is quite possible to have a fermionic atom with a bosonic nucleus. Take, for example, Nitrogen-14. The 14, or course, means it must have 14 nucleons, making the nuc
Re:I suppose it makes sense to physicists (Score:2)
I thought that, for example electrons, could have a -1/2 and +1/2 spin?
Re:I suppose it makes sense to physicists (Score:2, Informative)
But spin is a vector -- it can point in any direction in space. Thus it has a direction too (hence the plus or minus).
That answers your question, but at this point you might wonder why it is assigned either plus or minus 1/2 and not any arbitrary vector. The answer is that due to the weirdness of the spin space (that is, where the electron's spin "lives"), it can be described as a proj
Re:I suppose it makes sense to physicists (Score:3, Informative)
As the saying goes, I don't think those words mean what you think they do.
Fermions and bosons are only defined in the context of more-that-one-particle states. One-particle states couldn't care less. The idea is that for identical particles, a particle permutation has to be a valid symmetry of the system (after all, you can't tell t
Re:From wikipedia (Score:2)
Hope I got al