Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

String Theory Predicts Behavior of Superfluids

kdawson posted more than 5 years ago | from the good-for-something dept.

Math 348

schrodingers_rabbit writes "Despite formidable odds, condensed matter physicists have made a breakthrough most thought impossible — finding a practical use for string theory. The initial breakthrough was made by physicist and cosmologist Juan Maldacena. His theory states that the known universe is only a 2D construct in anti-de-Sitter space, projected into 3 dimensions. This theory manages to model black holes and quantum theory congruently, a feat that has eluded scientists for decades; but it fails to correspond to the shape of space-time in the known universe. However, it does predict thermodynamic properties of black holes, including higher-dimensional viscosity — the equations for which elegantly and almost exactly calculate the behavior of quark-gluon plasma and other superfluids. According to Jan Zaanen at the University of Leiden, 'The theory is calculating precisely what we are seeing in experiments.' Unfortunately, the correspondence cannot prove or disprove string theory, although it is a positive step." Not an easy path to follow: one condensed matter theorist said, "It took two years and two 1000-page books of dense mathematics, but I learned string theory and got kind of enchanted by it. [When the string-theory related] thing began to... make predictions about high-temperature superconductors, my traditional mainstay, I was one of the few condensed matter physicists with the preparation to take it up."

Sorry! There are no comments related to the filter you selected.

Yeah... (5, Interesting)

paazin (719486) | more than 5 years ago | (#28221675)

Unfortunately, the correspondence cannot prove or disprove string theory, although it is a positive step.

That is to say, if you view that the proving of string theory to be true a positive step.

Re:Yeah... (5, Insightful)

samriel (1456543) | more than 5 years ago | (#28221699)

Enlighten me, why would proving a theory that is another step toward a GUT be a negative step?

Re:Yeah... (5, Funny)

FredFredrickson (1177871) | more than 5 years ago | (#28221837)

Enlighten me, why would proving a theory that is another step toward a GUT be a negative step?

Well, you see, string theory is very complex, but really in the 2d universe we truly live in, it can be considered a negative step, but you won't understand it, because your used to only experiencing the 2 real dimensions and the incredible faux 3rd dimension, which is a construct of our brains to understand the space which we perceive. Anyway, the point is, if you really understand string theory, you see the negative step. But if you're standing behind the theory, it's a positive step. It's all relative.

Re:Yeah... (Score:1) Mod Parent +1 WTF? POP-PHYSICS

Re:Yeah... (1, Insightful)

Anonymous Coward | more than 5 years ago | (#28222027)

Parent Summarised:
"I don't like what it could mean, therefore, it's a negative thing."

Re:Yeah... (5, Interesting)

jandoedel (1149947) | more than 5 years ago | (#28221845)

if string theory is disproven, then we also know something more: the GUT is not string theory, ergo we need to direct our energy towards finding another theory. string theory is kinda unelegantly difficult, so a lot of people don't really want it to be true.

Re:Yeah... (0, Troll)

fulldecent (598482) | more than 5 years ago | (#28221883)

Chicken fingers. That's my grand unified theory.

It taking another step towards that theory good?

Re:Yeah... (2, Funny)

db10 (740174) | more than 5 years ago | (#28222107)

Chicken don't have fingers, I hope this fact doesn't affect your PhD thesis.

Re:Yeah... (1)

cabjf (710106) | more than 5 years ago | (#28222159)

Next I suppose you're going to tell me buffalo don't have wings.

Re:Yeah... (2, Insightful)

Abcd1234 (188840) | more than 5 years ago | (#28222369)

It taking another step towards that theory good?

If it's correct, then yes, of course. Good luck with your chicken finger theory!

Re:Yeah... (1)

Polir (675291) | more than 5 years ago | (#28221875)

I suspect that you are just trolling and you perfectly understand that the statement only tries to emphasise that: even that the calculations by this theory corresponds with experimental data it does not prove the theory true, although it is a positive step (so it at least doesn't contradicts). And that this has nothing to do with wheter string theory itself a "positive step" to anywhere or not.

Re:Yeah... (0, Troll)

Anonymous Coward | more than 5 years ago | (#28222023)

A bit of a side point, you can never prove a theory no matter how much biologists (or anyone else) claims differently, you can only uncover evidence that supports it. However you can disprove a theory quite easily just by finding one case that doesn't fit with the theoretical predictions.
This is what makes evolution a bad theory and creationism a much worse one, neither makes concrete testable predictions. String theory falls in the same category, no testable predictions. The summery (because this is /. and we don't read articles here) just says that the mathematics from string theory has been used to model already observed behavior. Neat idea but until the mathematics makes a testable prediction that matches the followup experiments, it is just masturbation with numbers.
Yes I have my phd in theoretical soft condensed mater physics and work in a research lab.

Re:Yeah... (0)

Anonymous Coward | more than 5 years ago | (#28222077)

How does your mother feel about you converting her into a soft and condensed form, like custard? Meh, probably doesn't matter.

Re:Yeah... (5, Informative)

EL_mal0 (777947) | more than 5 years ago | (#28222085)

Stick to physics; evolution does make testable predictions. It usually takes a while to run the tests, though.

Re:Yeah... (1, Informative)

Anonymous Coward | more than 5 years ago | (#28222109)

Evolution certainly makes concrete, testable predictions: about what we expect to see in the fossil record, about what we expect to see in the genetic makeup of various species, about what we expect to see in the phenotypic features and behaviors of modern species, and about how we expect species to change over time. As a simple example of the last, consider http://www.ted.com/index.php/talks/paul_ewald_asks_can_we_domesticate_germs.html

Re:Yeah... (4, Informative)

Anonymous Coward | more than 5 years ago | (#28222495)

This is what makes evolution ... neither makes concrete testable predictions.

Really?
http://en.wikipedia.org/wiki/Tiktaalik#Discovery

"It's one of those things you can point to and say, 'I told you this would exist,' and there it is."

Re:Yeah... (2, Insightful)

elashish14 (1302231) | more than 5 years ago | (#28222563)

Unfortunately, the correspondence cannot prove or disprove string theory, although it is a positive step.

That is to say, if you view that the proving of string theory to be true a positive step.

Pardon me for the semantics, but no science/scientific theory can be "proven" - even the theory of gravity can't be proven. If I take a rock and drop it on my desk a million times, that doesn't prove that it'll fall there again on the 1e6+1th time. The same goes with the theory of evolution: nothing can prove evolution, but we just have a lot of evidence (fossils, experiments, etc.) that support it. A theory is supposed to make robust predictions, not sense. You can't understand science, you can only apply it. Classical mechanics can't make sense of blackbody radiation or the photoelectric effect, but that doesn't mean that it's wrong, just that it's not useful on a quantum scale. String theory itself probably only has some realm of physics/dynamics that only it can explain that just doesn't make sense/isn't useful in the realm that we try to understand it in now.

Re:Yeah... (4, Insightful)

gartogg (317481) | more than 5 years ago | (#28222773)

Your point about semantics and the word proof is understood. Of course, you are conflating proof in a mathematical sense with scientific proof. Scientific theories are proven repeatedly, when testable predictions are confirmed. (This is the traditional use of the word in science) They can still be disproven, but scientific proof is very different than mathematical proof. Of course, proof in the common sense meaning of the word is a completely different idea, and yet a third thing. If you're going to make semantic points, make sure the words you use are the ones you want. "Proof" is a bad one to pick apart semantically, because there are a couple different meaning depending on context and meaning. (Yes, in the same context, the same word can mean 2 different things. That's language for you.)

Of course, you then stop making sense. One CAN understand science. See many comments of Feynman about just that point.You may think you are a scientist, but you seem to think about science a hell of a lot like an engineer.

Science Fiction (2, Insightful)

siloko (1133863) | more than 5 years ago | (#28221689)

Is it just me or does String Theory really sound like someone is making it up as they go along. It's like: "we haven't a clue whats going on but reality's so wierd we've decided to pull a theory out of our ass!"

Re:Science Fiction (4, Insightful)

Anonymous Coward | more than 5 years ago | (#28221737)

Umm, you've just described all scientific progress both past, present, and future...

Re:Science Fiction (1, Insightful)

Anonymous Coward | more than 5 years ago | (#28221957)

I thought "both" was only used to describe two items.

Re:Science Fiction (5, Funny)

nomorecwrd (1193329) | more than 5 years ago | (#28222083)

That's because your mind is still constrained by our 2D universe.

Re:Science Fiction (0)

Anonymous Coward | more than 5 years ago | (#28221751)

And pulling it out with strings!

Sorry about that...

Re:Science Fiction (0)

Anonymous Coward | more than 5 years ago | (#28221757)

It's not just you. It's almost a cult thing within the scientific community, and isn't particularly well-regarded even as a theory...it's borderline unfalsifiable pseudoscience.

Re:Science Fiction (-1, Redundant)

Anonymous Coward | more than 5 years ago | (#28221803)

That's what upper-level science is. One can become so fluent in a language that they can spin a tale and manipulate the rules of the language to explain what is said. For example:

Kill the children
Save the food
They're nothing but a bunch of black jig-a-boos

Save your money
Let 'em die
So we can snort dope and get fuckin' high.

Re:Science Fiction (1)

ZombieWomble (893157) | more than 5 years ago | (#28221809)

Yeah, not like all that good science which is decided in advance and then rigidly adhered to!

Wait a minute...

Re:Science Fiction (1, Funny)

Anonymous Coward | more than 5 years ago | (#28221847)

It's like spaghetti theory. They throw bunch up against wall, and if a few sticks then they say "see, like we were saying...".

Doesn't matter. They'd all soon be hanged with FSM tentacles for sacrilege.

Re:Science Fiction (1)

mikael (484) | more than 5 years ago | (#28221849)

I think astrophysics is like that - I once went into a university bookstore to buy some recommended textbooks. On the top of the discount book table was a really impressive looking book with a some wireframe graphics on the front page. It was a summary of all the research carried out on the mathematical theory of black holes over 10 years (the size of two PC keyboards back to back). It was being sold at a discount because all the research was now out of date.

Re:Science Fiction (4, Funny)

m.ducharme (1082683) | more than 5 years ago | (#28222149)

I'm sorry, I'm not familiar with "pc keyboards back-to-back" as a system of measurement, could you translate that into Football Fields for me?

Re:Science Fiction (1)

AliasMarlowe (1042386) | more than 5 years ago | (#28222951)

I'm not familiar with "pc keyboards back-to-back" as a system of measurement

About 14 of these would make a kilderkin. About 200000 of them would make an acre-foot.
Everything clear now?

Re:Science Fiction (0)

Anonymous Coward | more than 5 years ago | (#28222081)

I know people that pull Strings out of their ass...., but usually beads are attached to them.

Re:Science Fiction (1)

Prof.Phreak (584152) | more than 5 years ago | (#28222129)

Exactly! Who the heck even -knows- what string theory really is? (beyond the pop-sci ``we model things as strings instead of point particles'').

From what I've read, the equations are so broad that you can calculate and fit'em to pretty much anything (sorta like you can calculate anything with a general purpose computer...therefore, the computer is a physics theory---it calculates things so exactly!)

The problem of string theory isn't its ability to predict. It's falsifiability. I've yet to see an experiment (or even an -idea-) that -could- prove string theory wrong. Without that little bit, it's not a theory at all... it's a... religion!

Re:Science Fiction (2, Insightful)

Draek (916851) | more than 5 years ago | (#28222235)

To be fair, the same could be (and was) said of Quantum Physics as well. Reality *is* fucked up after all.

Pity, Newton's equations were *so* much easier...

Re:Science Fiction (1)

Troed (102527) | more than 5 years ago | (#28222557)

It's becoming harder and harder for the ones controlling our simulation to keep up the impression of a live dynamic world. Having to stay one step ahead of our scientific progress in the simulated world, having to explain phenomena that were once thought out of our grasp yet documented (distant galaxies with the same rotation speed regardless of the distance from the core) and now needing explanations.

We're close to seeing the illusion fail. I wonder if that makes the experiment invalid and if they'll just pull the plug?

[yeah, totally insane, but what if?]

Re:Science Fiction (1)

Abcd1234 (188840) | more than 5 years ago | (#28222415)

No, it isn't just you. A lot of ignorant, know-it-all, non-physicist Slashdotters have made the same complaint.

Re:Science Fiction (1)

elashish14 (1302231) | more than 5 years ago | (#28222505)

That's all science ever is. Nobody knows what a wavefunction is supposed to be, but it's the core element of quantum mechanics and it's incredibly useful. Nobody really understand what entropy is either, or how you're supposed to understand things like enthalpy or Gibbs/Helmholtz free energy, but they're still essential for determining equilibrium systems/structures via thermodynamics and statistical mechanics. The value of a theory is based on how much it explains and whether it makes any useful, verifiable and applicable predictions. So yes, in essence, you're right but your misunderstanding is more of what science is as opposed to string theory.

Re:Science Fiction (1)

kalirion (728907) | more than 5 years ago | (#28222857)

That's what I think about Dark Matter / Energy.

Re:Science Fiction (0)

Anonymous Coward | more than 5 years ago | (#28222875)

Speaking, like most people on slashdot, as someone who has absolutely no knowledge of the topic other than what I have read in the summary, I agree 1,000,000%. Science is useless, any scientific theory I don't understand is a hoax or a religion, Ron Paul is electable, and 9/11 was an inside job.

Title (0)

Anonymous Coward | more than 5 years ago | (#28221703)

I have a theory that there must be a joke in here somewhere about strings and superfluid!

Re:Title (2, Funny)

BadAnalogyGuy (945258) | more than 5 years ago | (#28221799)

I have a theory that there must be a joke in here somewhere about strings and superfluid!

Maybe something about David Carradine or Michael Hutchence?

O.o (1)

Nickodeimus (1263214) | more than 5 years ago | (#28221723)

is string theory something to do with that thing in space in Star Trek: Generations?

Re:O.o (2, Funny)

Rashdot (845549) | more than 5 years ago | (#28222251)

I don't know, but I do have a theory how 7of9 would look in a string.

Re:O.o (1)

robinsonne (952701) | more than 5 years ago | (#28222555)

IIRC, that was a ribbon, not a string.

Wow (4, Interesting)

pzs (857406) | more than 5 years ago | (#28221727)

I'm always amazed that theoretical physicists can manipulate such immensely complex abstract objects in their heads and still be able to breathe and maintain bladder control. It really makes software engineering look like a piece of piss. Much respect.

I would also say that having worked with academic medics, chemists, mathematicians, computer scientists and biologists, physicists are almost always the coolest, most down to earth and least douchey scientists out there.

Re:Wow (4, Insightful)

Anonymous Coward | more than 5 years ago | (#28222045)

It's because they look at how huge the universe is, how much energy is in it, how long it's all been around, how long it will most likely continue to be around, then truly comprehend how small, short-lived, and insignificant they are in the grand scheme of things.

That kind of realization will humble anyone, no matter how smart they are.

Re:Wow (5, Insightful)

Fnkmaster (89084) | more than 5 years ago | (#28222079)

Very simple explanation - nothing in the universe builds humility like an education in physics. If you don't walk out of a physics degree feeling like you know less than you did when you started, like all you've done is build layer upon layer of model and gained only modest flashes of insight into reality after marathon sessions of math, then you've done something wrong.

Re:Wow (1, Troll)

Hecatonchires (231908) | more than 5 years ago | (#28222101)

Have you met old scientists? Smelly old men with irritable bowel and asthma.

You just described "old people" (-1)

Anonymous Coward | more than 5 years ago | (#28222255)

They ALL have irritable bowel and asthma.

Only a 2D construct in anti-de-Sitter space! (5, Funny)

Dystopian Rebel (714995) | more than 5 years ago | (#28221753)

the known universe is only a 2D construct in anti-de-Sitter space, projected into 3 dimensions

Well if THAT'S all it is, I see no reason to upgrade my video card.

Re:Only a 2D construct in anti-de-Sitter space! (1)

MoldySpore (1280634) | more than 5 years ago | (#28221859)

True, but DirectX 11 will support anti-de-Sitter 3D Projection Model 1.0 so you'll have to upgrade eventually. ;)

The guys over @ "The Big Bang Theory" are probably scrambling to incorporate this into next season's scripts. Pretty much the only practical application of String Theory for the rest of us.

Re:Only a 2D construct in anti-de-Sitter space! (5, Funny)

L4t3r4lu5 (1216702) | more than 5 years ago | (#28222021)

Indeed. I hadn't heard of the term before, so I looked it up.

In mathematics and physics, n-dimensional anti de Sitter space, sometimes written AdSn, is a maximally symmetric Lorentzian manifold with constant negative scalar curvature. It is the Lorentzian analog of n-dimensional hyperbolic space, just as Minkowski space and de Sitter space are the analogs of Euclidean and elliptical spaces respectively. It is best known for its role in the AdS/CFT correspondence.

- http://en.wikipedia.org/wiki/Anti_de_Sitter_space [wikipedia.org]

Well, glad that's cleared up!

Re:Only a 2D construct in anti-de-Sitter space! (5, Funny)

ColdWetDog (752185) | more than 5 years ago | (#28222301)

Yeah, I looked at that Wikipedia article. Then I had to look up all of the other words.

Then my head asplode.

Thanks a lot!

Re:Only a 2D construct in anti-de-Sitter space! (5, Insightful)

nyctopterus (717502) | more than 5 years ago | (#28222411)

Gah! That's so common in technical topics on Wikipedia. The problem is that it is is written by undergrads and interested amateurs (I know, I'm one of them). Often they don't know the subject well enough to simplify it for a general audience, and are stuck putting it in the same language they learned it in. Simplifying a complex topic generally takes quite a degree of mastery, in order to know which simplifications are justifiable, and which would distort the concept too much.

Also, I think sometimes they like to show off by writing things people can't understand.

Re:Only a 2D construct in anti-de-Sitter space! (4, Informative)

Timmmm (636430) | more than 5 years ago | (#28222667)

"Also, I think sometimes they like to show off by writing things people can't understand."

Definitely. E.g. the intro for "dot product" says "It is the standard inner product of the orthonormal Euclidean space." If you're trying to work out what a dot product *is* then that is a completely useless and confusing statement. Mathworld is usually much better than Wikipedia in this respect.

Re:Only a 2D construct in anti-de-Sitter space! (-1, Troll)

Anonymous Coward | more than 5 years ago | (#28222947)

Well just because your half-neuron has problems in understanding that does not mean we have to stupefy every useful encyclopaedia.
Try simple English wiki if you have any problem and leave the intelligent articles to intelligent people!

Re:Only a 2D construct in anti-de-Sitter space! (1)

berashith (222128) | more than 5 years ago | (#28222781)

my two year old son can beat the shit out of a keyboard and write something that people cant understand. It is no reason to show off!

Ah so the world is flat (0)

Anonymous Coward | more than 5 years ago | (#28222417)

See live long enough and you do get proved right now how do they explain the horizion?

It's the math, stupid (5, Interesting)

BadAnalogyGuy (945258) | more than 5 years ago | (#28221755)

String theory works because the math works. There isn't anything special about the string theorists' model of humming cosmic strings that makes it work. All particle behavior is explainable using mathematics.

What makes this interesting is that the model allowed for the construction of mathematical constructs that explain the behavior correctly. But it still doesn't say anything about the predictions that the model completely blows.

What String Theory has, more than anything else, is a great set of marketeers behind it. Michio Kaku is a smart and articulate guy. It's not the steak, it's the sizzle.

Re:It's the math, stupid (1, Interesting)

Anonymous Coward | more than 5 years ago | (#28221823)

I'd also blame Brian Greene. It's something that sounds vaguely sexy and can be BS'd to the public who can't possibly understand the mathematics (I can't either).

But it doesn't seem to actually advance scientific knowledge in any way. And I've yet to see anyone propose a realistic experiment that could disprove it. Which puts it on par with, at best, philosophy.

Re:It's the math, stupid (1)

Prof.Phreak (584152) | more than 5 years ago | (#28222275)

...the public who can't possibly understand the mathematics (I can't either).

That's the beauty of it... nobody does! In fact, I have a theory on that too... but it would take two 1000 page books to express it.

Re:It's the math, stupid (1)

GMFTatsujin (239569) | more than 5 years ago | (#28222407)

Why not just write about it in the margin, like that other smart math guy?

Re:It's the math, stupid (0)

Anonymous Coward | more than 5 years ago | (#28221863)

that's such BS. I'll bet you don't even know the difference between a cosmic string and a cosmic filament.

Re:It's the math, stupid (5, Insightful)

Fnkmaster (89084) | more than 5 years ago | (#28222115)

Any statistician will tell you that if you put enough free parameters in a model, you can calibrate it to the given data. Admittedly, string theory has some impressive parts to it, but it seems like it's just excess parameter fitting for a class of models that can all explain roughly the standard model.

But if somebody does come up with a particular string-theoretic model with new, testable implications that get verified that would be impressive - it would certainly indicate that they are barking up the right tree rather than just working on a pleasant geometric abstraction that can be set up to reduce to the messy realities of our fundamental forces and particles.

Re:It's the math, stupid (3, Informative)

Normal_Deviate (807129) | more than 5 years ago | (#28222253)

Parent post is insightful. If a model is flexible enough, it can fit any data.

Re:It's the math, stupid (1)

Abcd1234 (188840) | more than 5 years ago | (#28222341)

If a model is flexible enough, it can fit any data.

Wrong. If a model is flexible enough, you can probably make it fit a given set of data. But *all* data? No. If it could fit all data, it would be an *accurate model*... which is precisely what they're striving for.

Re:It's the math, stupid (1)

bothemeson (1416261) | more than 5 years ago | (#28222503)

Parent post is insightful. If a model is flexible enough, it can fit any data.

----------
Court Philosopher to our Robotic - and never stringy - Overlords!

Re:It's the math, stupid (2, Funny)

Alzheimers (467217) | more than 5 years ago | (#28222663)

Strings ARE flexible! You can even tie them in knots.

Re:It's the math, stupid (3, Insightful)

m.ducharme (1082683) | more than 5 years ago | (#28222193)

So where's the competing theory, the one that explains things better, and is testable and whatnot? I hadn't heard that there really was one. My impression was that the one advantage the String theorists have is that they currently don't have any credible competition, though I confess that I haven't been keeping up with the debates.

But... (4, Funny)

HaeMaker (221642) | more than 5 years ago | (#28221781)

on page 642 of the second book, they divide by zero, so back to the drawing board.

Re:But... (4, Funny)

L4t3r4lu5 (1216702) | more than 5 years ago | (#28222089)

That's ok, Chuck Norris helped them out with that bit. He said it was ok, and if the universe didn't like it, it could meet him outside.

So far, Chuck's out there by himself.

Re:But... (1)

OneSmartFellow (716217) | more than 5 years ago | (#28222111)

Frink: Oh, I forgot to er, carry the one.

Exciting (3, Funny)

Rosco P. Coltrane (209368) | more than 5 years ago | (#28221793)

one condensed matter theorist said, "It took two years and two 1000-page books of dense mathematics, but I learned string theory and got kind of enchanted by it.

Boy, long winter evenings must just fly.

String theory started as a theory of QCD (1)

PvtVoid (1252388) | more than 5 years ago | (#28221911)

String theory was originally conceived as a theory for QCD, and only later was it applied to quantum gravity. Here (http://physics.aps.org/articles/v1/10 [aps.org] ) is an article which explains the new results with a little historical context.

Poster doesn't understand TFA (5, Informative)

disputationist (1324927) | more than 5 years ago | (#28221941)

The Maldacena duality can't be used to 'make predictions' with a string theory, its just a correspondence between a string theory and a conformal field theory. It's useful because sometimes calculations which are hard in a CFT can be made in the corresponding string theory which is sometimes easier (or vice versa). It cannot be used to support the physical validity of some string theory.

I lol'd (5, Funny)

Anonymous Coward | more than 5 years ago | (#28221945)

The current tags (in order) for this story read to me:

mygoddoyouknowwhatthismeans noidont stoptalkingintags

Of course... (1)

M-RES (653754) | more than 5 years ago | (#28221967)

I read TFA and just thought "as you do..."

Surely any discovery, either for or against prior ideas is a step forward and thus positive. It's the scientific method - proving yourself wrong is just as big a success as proving yourself right. It's the proof that is important :)

I don't understand (0)

Anonymous Coward | more than 5 years ago | (#28221973)

No, really I don't. "space-time has any number of dimensions, usually 10" USUALLY?! What is anti-de-Sitter space anyway? What? WHAT? WHAT THE FRELL?!?!!111one

Re:I don't understand (1)

Yvan256 (722131) | more than 5 years ago | (#28222067)

Simple answer to all your questions: 42.

Re:I don't understand (1, Insightful)

Anonymous Coward | more than 5 years ago | (#28222191)

How many times till this joke becomes lame?

Re:I don't understand (0)

Anonymous Coward | more than 5 years ago | (#28222345)

42?

Re:I don't understand (4, Funny)

dim5 (844238) | more than 5 years ago | (#28222371)

Oh, I think you know the answer to that.

Re:I don't understand (0)

Anonymous Coward | more than 5 years ago | (#28222463)

How many times till this joke becomes lame?

I'm guessing 42

Re:I don't understand (1)

zzsmirkzz (974536) | more than 5 years ago | (#28222733)

The interesting thing about the number 42 and it's relevance to Life, the Universe and Everything, is its representation in binary which is "101010". Basically, it's the simplest demonstration of an oscillation which continued would go on forever... So what is the meaning of Life, the Universe and Everything?? Simply that it continues to exist.

Wow, the theory that matches all experimental data (1)

Culture20 (968837) | more than 5 years ago | (#28221987)

except the datum of there being _at_least_ 3 spatial dimensions.

Re:Wow, the theory that matches all experimental d (5, Interesting)

JustinOpinion (1246824) | more than 5 years ago | (#28222237)

The holographic principle [wikipedia.org] doesn't mean that the universe has only 2 spatial dimensions, but rather that the universe can be modeled using one less degree of freedom than our view of spacetime would imply. Again, these kinds of theories are not suggesting that our space is two-dimensional, rather they are saying that the 3 dimensions we observe are emergent from a lower-dimensional description. All of the 'information' in a given region of space can be described as being encoded in the surface of said region.

This remarkable, if bizarre, conclusion gains considerable support from the fact that black-hole entropy [wikipedia.org] (and entropy is a measure of information content) is related only to the surface area of the black hole. So this is a case where we know with some confidence that we can indeed reduce all the information about a 3D region of space (the black hole) to an expression that only relies on 2 dimensions (the surface of the black hole). The holographic principle appears in numerous theories that imply that this holds generally for any region of space, not just black holes.

Now, whether you view this is 'just a mathematical trick' or 'a deep insight into the actual structure of the universe' is in some sense a matter of taste. (The same goes for all other physical theories: e.g. do electrons exist or are they just mathematically-useful constructs? How about photons? Gravity waves? Spacetime?) If you take the math seriously then this may mean that our universe is in some sense 'actually' 2-dimensional, with the three spatial dimensions we see being emergent instead of fundamental.

But in no case is the theory saying that there are not 3 spatial dimensions. The predictions it makes are for particles moving through a 3+1 spacetime.

Re:Wow, the theory that matches all experimental d (1)

Teese (89081) | more than 5 years ago | (#28222599)

The parent needs a higher score pronto. Hopefully a fundamental score of +5 insightful, and not an emergent one of +4 interesting +1funny

I have no idea what I'm saying.

catching up to 18th century theorists (-1, Troll)

peter303 (12292) | more than 5 years ago | (#28222075)

This was worked out 250 years ago in the Newtonian framework.

Re:catching up to 18th century theorists (0)

Anonymous Coward | more than 5 years ago | (#28222729)

Source/reference?

Almost exactly (1)

fbilsen (549231) | more than 5 years ago | (#28222091)

hehe...almost exactly...doesn't seem to be correct then...

nerds (0)

Anonymous Coward | more than 5 years ago | (#28222127)

i just uninstalled your linux.

Explaining is not predicting (3, Interesting)

Normal_Deviate (807129) | more than 5 years ago | (#28222203)

The main criticism of string theory is that it is too flexible. It can be contorted to generate any prediction, so it predicts nothing. This problem is not unique to physics; I saw it in economics too. Add more parameters to your model and you can fit historical data better, but your predictions of the future get worse. TFA seems to be just a string of examples of contorting string theory to fit past experimental results.

Re:Explaining is not predicting (1)

digitig (1056110) | more than 5 years ago | (#28222661)

Yes, that was my thought too. This work hasn't predicted anything at all, it's simply consistent with what was already known. To predict it has to tell us something we don't know that then turns out to be the case.

Ah! (1)

jav1231 (539129) | more than 5 years ago | (#28222213)

But can it predict superfluity?

:P

Re:Ah! (1)

bothemeson (1416261) | more than 5 years ago | (#28222595)

But can it predict superfluity? :P

Well economics really should, the current economic climate is fairly fluid, no?

----------

Court Philosopher to our Robotic - and never stingy - Overlords!

Give it time (3, Insightful)

elashish14 (1302231) | more than 5 years ago | (#28222453)

Everybody gives string theory a hard time because it hasn't made any predictions, and because it can't be tested. Give it some damn time. It took ages before anyone could make useful predictions with quantum mechanics, and it was shunned for a while too (even by Einstein) and now it's an essential part of our scientific understanding. We shouldn't be so quick to cast out string theory either. Some time, eventually, maybe very far down the road (and if it turns out to be right), it too could be as useful as quantum mechanics has become. I wish scientists would just open their damn minds for once.

Re:Give it time (1)

jandoedel (1149947) | more than 5 years ago | (#28222721)

a) Einstein didn't shun quantum mechanics, in fact he was one of the people who invented QM b) it didn't take ages to make useful predictions, it made useful predictions starting from day 1

String Theory Predicts Something? (2, Interesting)

hAckz0r (989977) | more than 5 years ago | (#28222465)

Ok, I'll bite, which one? There are NUMEROUS 'String Theories' and they don't all mean the same thing. In fact I will be happy when the day comes that there is some kind of a 'Unified String Theory' so there is enough of it all in one place to be able to *disprove* something. Its kind of hard to prove that ten gallons of Jello won't fit in a bottle half its size if you can't get it all in one place at one time. You can't disprove something that you have not even sufficiently defined either.

The major problem with String/F/D/Dn/S/Brane/M/Multiverse/Whatever's-next Theory is that every time someone finds a problem that doesn't fit with experiments/reality they just go and find an excuse and then modify the equations until it mathematically works out in that general direction. They don't start with the latest and greatest and modify that. They just pick their favourite Theory-of-the-day and add an extra dimension here, or there, twist it there, or subtract another infinite from both sides, because the formula is inconveniently looking incorrect at the moment. In other words, Just squish the Jello a little here and make it come out over there instead, until someone discovers 'the new mess' on the floor.

If a theory has no basis in fact (i.e. no physical reality that can be described) then it is just Math. Math is not reality. You can model anything with Math, and it doesn't even have to exist.

Re:String Theory Predicts Something? (5, Insightful)

JustinOpinion (1246824) | more than 5 years ago | (#28222819)

You are contradicting yourself. You say:

The major problem with String/F/D/Dn/S/Brane/M/Multiverse/Whatever's-next Theory is that every time someone finds a problem that doesn't fit with experiments/reality they just go and find an excuse and then modify the equations

but then complain:

If a theory has no basis in fact (i.e. no physical reality that can be described) then it is just Math.

If theorists are continually modifying their theories in order to fit with experiment/reality, and rejecting theories that don't fit with experiment/reality, then what's the problem? At that point it's not "just math", it's "math that correctly matches reality and makes predictions", which is the gold-standard in physics.

Now, you may disagree with the particular mathematical formalisms the theorists are investigating, or the particular order in which they are checking them... but I don't understand how you can be upset at them for continually making changes in order to fit their theories with reality. That's what theorists are supposed to do: investigate a wide and wild variety of mathematical theories, and see which ones are able to make useful predictions consistent with experiment.

They just pick their favourite Theory-of-the-day and add an extra dimension here, or there, twist it there, or subtract another infinite from both sides, because the formula is inconveniently looking incorrect at the moment.

Again, this is an objection of procedure. If you can think of a faster way to uncover a mathematical theory consistent with all known experiments, then describe it. Until then, what's wrong with theorists checking a wide variety of theories (adding and subtracting terms/elements/dimensions as they go) until they find one consistent with observed reality?

(And of course, in reality theorists are not performing the random-walk through theory-space you describe. They have very good reasons for checking the equations they do; their analysis is informed by many experimental results, previously-successful theories, and the structure of mathematics itself.)

Re:String Theory Predicts Something? (0)

Anonymous Coward | more than 5 years ago | (#28222835)

If a theory has no basis in fact (i.e. no physical reality that can be described) then it is just Math. Math is not reality. You can model anything with Math, and it doesn't even have to exist.

Unless what we believe (or model) has more to do with reality than anything physical.

mind-boggling folding (1)

muntis (1503471) | more than 5 years ago | (#28222625)

Folding 10 dimensions down to four can be done in a mind-boggling 10^500 ways

Jeah, I'm not a physicist and I know, that I'm spoiling my karma right now, but seams that they just made up some very generic "function" with N attributes and every time result does not match, they say- "Hei, change that attribute" or "Take 8 dimensions instead of 10" or "Fold 5th dimension that way". Come on, even y = ax^2 + bc + c almost match with y=sin(x) in some particular region of x if you set up a's, b's and c's correctly.

Superfluid? (0)

Anonymous Coward | more than 5 years ago | (#28222945)

You're a non-Newtonian fluid
The kind you can't take home to moth-tha.

Load More Comments
Slashdot Login

Need an Account?

Forgot your password?