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strung theory
March 16, 2005 2:19 AM   Subscribe

"A theory that can't predict anything is not a scientific theory," Woit says. That would be string theory, which was going to be the theory of everything, but apparently can't even agree how many dimensions there are. "Those who dabble in alternate-universe speculations might be just modern versions of '16th century theologians (who) speculated that spirits and angels emerge from the extra-dimensional universe,' says Krauss, who is also an outspoken foe of creationist teaching in schools."
posted by raaka (52 comments total)

 
A theory that can't predict anything is not a scientific theory

Scratch economics, then, and probably half of the social sciences.

16th century theologians (who) speculated that spirits and angels emerge from the extra-dimensional universe

*shrug* Consciousness has got to come from somewhere.
posted by weston at 2:54 AM on March 16, 2005


Bit of a one-sided post, raaka. The evidence for string theory is the evidence for quantum mechanics and general relativity. separately, those two pools of evidence produce their respective theories; together, they produce string theory. (And there's, hopefully, new evidence coming down the pike.)

"The physics department at Stanford effectively fissioned over this issue," said Laughlin, now on sabbatical in South Korea. "I think string theory is textbook 'post-modernism' (and) fueled by irresponsible expenditures of money."

I'd argue that the truer postmodernists are those who say there's no need for a unified theory, that separate realms are fundamentally incompatible. Since its birth in Newton, physics has been a science of unification: Newton realized that a falling apple and an orbiting planet were doing exactly the same thing. Saying there's no need for TOE is sloppy thinking. When you feel the keyboard, quantum interactions are converted into (slightly) larger-scale signals that travel to your brain; when you decide to press a key, your brain sends signals to your hand, which moves -- a huge, macroscopic movement. Quantum to non-quantum. There aren't hard borders between conceptual realms (of size, etc.); the universe is all one thing, and it needs one set of laws.

That might be a straw man; I don't know if Laughlin is in that camp, but -- as far as I can tell -- the only physicists in it are non string theorists.

Over the last two decades, a generation of brilliant young physicists -- the kinds of proto-Einsteins who historically have led intellectual revolution after revolution -- has flocked to string theory because their professors told them that's where the action was

Oh, come on. They flocked to string theory because string theory is intellectually exciting.
posted by Tlogmer at 3:22 AM on March 16, 2005


And a nitpick, but you misquoted the article: the only part the scientist said was "16th century theologians (who) speculated that spirits and angels emerge from the extra-dimensional universe"; the reporter added the "might be" and everything else (presumably paraphrasing).
posted by Tlogmer at 3:26 AM on March 16, 2005


How do they expect string theory to ever generate predictions if all the brilliant young physicists ignore it?

String theory is one interesting explanation that could unify Einstein's model and quantum mechanics. It is a long way from being the accepted model, but it is not necessarily evil. What exactly is this guy arguing, that we should abandon it because it hasn't been proven yet?
posted by sophist at 3:39 AM on March 16, 2005


Correction: He is arguing we should not pursue it because it essentially unprovable.

However " In his new book "Parallel Worlds" (Doubleday), Kaku disagrees and argues that the first experimental evidence for string theory might begin to emerge within several years from experiments with scientific instruments such as a new particle accelerator, the Large Hadron Collider, which opens for business near Geneva in 2007."

Give it a few years, who knows what they will come up with?
posted by sophist at 3:47 AM on March 16, 2005


There's a good discussion over at a Columbia mathematician's string theory blog, Not Even Wrong.
posted by Tlogmer at 3:59 AM on March 16, 2005


Wasn't relativity largely considered unprovable and irrelevant when Einstein (or his wife, depending on whom you believe) first came up with it?
posted by psmealey at 4:01 AM on March 16, 2005


Oh this is cool - I was just blogging the other day about how String Theory seems fishy.

For everyone upthread who is saying... "But wasn't theory X considered unprovable or controversial back in the day??" Well sure, you can make that comparison... but Relativity and Quantum Mechanics have both jibbed with real observations... with String Theory it's unlikely there are any observations to make.

String Theory is a great as traditional mythology goes... it can potentially explain reality without relying on gods or monsters... but if it can't be tested then it won't ever be anything other than a fancy myth.
posted by wfrgms at 5:10 AM on March 16, 2005


I'm no expert, but I tend to trust Brian Greene, because he is a multi-dimensional superbeing.
posted by Pretty_Generic at 5:15 AM on March 16, 2005


General relativity wasn't experimentally verified with new data until gravitational lensing of the sun was observed in (I think) 1921. But it already explained existing data better than competing theories. String theory is similar in that it reconciles GR and QM better than anything else we have, and may be tested with new data in the next few years.
posted by Tlogmer at 5:19 AM on March 16, 2005


Occam's Razor surrenders.
posted by HTuttle at 5:25 AM on March 16, 2005


I'm a proto-physicist who was once in love with string theory but has since done some philosophical growing-up and is no longer so enamored.

I still think string theory has a lot to offer. It is one of the better methods of unifying general relativity and the standard model (i.e. - unifying Einstein's gravity with the other interactions) and it has been shaking up a lot of pure mathematics as well: string theorists, rogues that they are, are finding results that more circumspect types like mathematicians would never have found were it not for the (admittedly tenuous) framework of string theory.

Still, it's important to realize that string theory isn't the only way to go about unification. The "loop" approach of folks like Ashtekar, Smolin, and Rovelli (who is quoted in the posted article, I believe) seems promising as well and there is, delightfully, even the supposition that the loop approach is related to or can complement the string approach.

The problem, as many have pointed out, is that all these newfangled theories suffer from a dearth of experimental clues. They are supposed to be describing physics some twenty or so orders of magnitude beyond anything we've ever experimentally probed. In such a regime, it's difficult, if not impossible, to differentiate between a theory that might offer some new and genuine physical insight and a theory which is just rampant speculation.

There's a feeling in the theoretical physics community, especially among those whose favorite philosopher is Kant, that if you're doing interesting mathematics then you're on the right track. Despite the undeniable arbitrariness of string theory in its present incarnation, it's definitely interesting and students will continue to flock to it, at least until something more interesting comes along. Is it a waste of brainpower? Probably not. Even if string theory turns out not to describe our world the consequence of all this hoopla will have been physicists eschewing physics for a while and working on mathematics, which isn't so bad at all. Is it a waste of money? Certainly not. Compared to the cash blown on giant particle accelerators like the LHC, funding for string theory essentially amounts to paying for chalk and blackboards.

Besides, for those like myself who are uncomfortable with wanton reductionism, there are a lot of interesting and non-stringy issues in theoretical physics that are just as important and just as difficult as string theory and the like.

On preview: Tlogmer, I don't know what tests of string theory in the next few years you're referring to but I suspect you're talking about the experiments at the LHC, scheduled to open in 2007. As far as I know, these aren't tests of string theory proper, but tests of other theories which string theory has subsumed and is now logically dependent upon. I think the way it works is that if they don't find what they're looking for (the Higgs boson, etc.) then string theory is in trouble, but if they do find what they're looking for, it's still not definite evidence for string theory.
posted by BaronEarth at 6:34 AM on March 16, 2005


OT: I had never heard this about the Bill Gates foundation:
And it disturbs me when someone like Bill Gates, whose philanthropy I otherwise admire, helps finance one of the major promoters of intelligent design by giving money to a largely conservative think tank called the Discovery Institute. Yes, they got a recent grant from the Gates Foundation. It's true that the almost $10-million grant, which is the second they received from Gates, doesn't support intelligent design, but it does add credibility to a group whose goals and activities are, based on my experiences with them, intellectually suspect. During the science standards debate in Ohio, institute operatives constantly tried to suggest that there was controversy about evolution where there wasn't and framed the debate in terms of a fairness issue, which it isn't. [Editors' note: Amy Low, a media relations officer representing the Bill and Melinda Gates Foundation, says that the foundation "has decided not to respond to Dr. Krauss's comments."]
posted by MonkeySaltedNuts at 6:56 AM on March 16, 2005


The evidence for string theory is the evidence for quantum mechanics and general relativity. separately, those two pools of evidence produce their respective theories; together, they produce string theory.

See, this is the kind of "overselling" that the article was talking about. It's true that string theory, in a certain limit, predicts the existence of linearized general relativity about a flat background. The problem is that gravity's not a linear theory, nor can spacetime be said to be flat in many interesting situations. To the best of my knowledge it hasn't been proven that the higher-order corrections actually add up in the proper way to produce the full, non-linear theory.

What's more, string theory is not the only candidate for a quantum theory of gravity out there; it's simply not true to say something to the effect that "if you put GR and QM in a blender and hit 'puree', you get string theory." In fact, it's probably more accurate to say that "if you put GR and QM in a blender, you get loop quantum gravity", since LQG grew directly out of an attempt to quantize general relativity, viewed as a field theory.

Don't get me wrong: I think that string theory is an interesting mathematical construct. But there are plenty of those in physics, and given the number of truly interesting results string theory has managed to produce so far (where I'm defining "interesting" here to mean "might have some relation to the real world"), it's really unclear to me why string theory is so revered in certain circles. But maybe I'm just a hidebound reactionary.
posted by Johnny Assay at 7:13 AM on March 16, 2005


A theory that can't predict anything is not a scientific theory

Scratch economics, then, and probably half of the social sciences.

Economics is a theory?
posted by Ayn Marx at 7:39 AM on March 16, 2005


Wasn't relativity largely considered unprovable and irrelevant when Einstein (or his wife, depending on whom you believe) first came up with it?

"Though Einstein based his theory of gravitation on deep theoretical principles, he and others proposed a number of experimental tests of the theory soon after its publication."

(further down on the same page) "Since almost two centuries earlier astronomers had been aware of a small flaw in Mercury's orbit around the Sun, as predicted by Newton's laws.... Mercury's elliptical path around the Sun shifts slightly with each orbit such that its closest point to the Sun (or "perihelion") shifts forward with each pass. Newton's theory had predicted an advance only half as large as the one actually observed. Einstein's predictions exactly matched the observation."
posted by DevilsAdvocate at 7:54 AM on March 16, 2005


I think so far the main achievements of the string and loop physical theories are the development of a lot of interesting math. See for example John Baez's finds.

A major problem with pure math is that mathematical structures are sort of like rabbits. They can be combined, generalized, refined, etc to produce a rapidly increasing collection of structures. As long as these new structures have something vaguely interesting about them and solid proofs behind them then their "discovery" is considered good math. Call this type of math the "expansion phase".

Better math happens when seemingly disparate notions are found to be equivalent or related. Call this type the "reduction phase".

Pure math doesn't really have any direction, the nearest thing to goals are various unsolved conjectures.

Math developed to serve physics is much more directed. Are there ways to reformulate classical physics, general and special relativity, quantum mechanics, etc to have some common basis? String and loop theories are attempts to do this. While such attempts yet have to succeed, the math behind creating such attempts has steadily gotten more refined, which makes creating new attacks all that much easier.

I feel such math is still not complete enough, and further mathematical development is necessary before some unification can succeed.

But then again, who knows? The tools may be at hand. When Einstien developed General Relativity, he used "tensors" which were unknown to practically all mathematicians and physicists (and this "new math" greatly blocked the theoretical understanding of GR).
posted by MonkeySaltedNuts at 7:58 AM on March 16, 2005


String theory seems more like a religious movement that relies on the fact that it cannot be disproved to perpetuate itself. The complex fields of math and science it is cloaked in make it doubly hard for the average person to see it for what it really is.

(I have serious beef with String Theory)
posted by DigDugDag at 8:14 AM on March 16, 2005


DigDugDag - it sounds like you're saying that since the average person can't necessarily understand something, that it isn't worth a damn? That's a remarkably dangerous attitude, I think.
posted by vernondalhart at 8:56 AM on March 16, 2005


Krauss is a physicist of the past. I know a couple of curmudgeonly old docs like him. To call String Theory unprovable is astounding ignorance. Is it hard to prove? Why yes, it is. But it can conceivably be done.

Anyone that thinks String Theory is unprovable really needs to get some damn perspective. It is not unique in the history of physics to propose a mathematical explanation for something seen, yet have that explanation require technologies beyond our current abilities to prove.

It is not, in any way, a "religious movement." It may very well be wrong, but if that is the case it will have always been science.
posted by teece at 9:18 AM on March 16, 2005


Nerd alert!
posted by bardic at 9:31 AM on March 16, 2005


DigDugDag - it sounds like you're saying that since the average person can't necessarily understand something, that it isn't worth a damn? That's a remarkably dangerous attitude, I think.

No I was saying that since that average person probably can't be knowledgeable of a lot of the principles String Theory brings up, there are fewer people who could make an honest evaluation of the theory. It's pretty easy for a theory like this to gain traction as long as books keep being published that skirt all the massive technical and logistical details.

The laymen is told to imagine strings guiding the universe. And it sounds great and it, as far as they know, could explain everything!

That's good visual concept, but it's hard to explain to people who just latch on to the visual concept the problems with, oh I don't know, having a theory that cannot be studied or proven in any way whatsoever. When you start to argue about extra dimensions the pool of people who can make an honest valuation of those theories shrinks rapidly.

The current interest in String Theory seems more like a marketing blitz than a breakthrough in the field of TOE. I'm not saying the theory is worthless if the common man cannot understand it, I'm saying it's not necessarily valid if the common man likes very much the sound of the theory.
posted by DigDugDag at 10:02 AM on March 16, 2005


Where I live -- in Waterloo, Canada -- they just opened a world-class Institute to study the foundations of quantum physics that includes the likes of Lee Smolin and Roger Penrose as founders.

From what I've seen and experienced talking to some of the researchers, the ones who support Loop Quantum Gravity and the ones who support Superstring theory don't have any antipathy towards each other.
posted by growli at 10:15 AM on March 16, 2005


Ok, what people need to know is that both String Theory and Loop Quantum Gravity accurately predict things on both ends of the spectrum, that is to say really tiny or really massive (as in heavy, not large), but both have problems that arise with really tiny and really massive (like black holes).

Keep in mind neither has the number of problems arising from singularity that QM or GR would have on their own. The sheer number of versions of string theory is an attempt to sort out those problems, and has made significantly more strides than LQG in doing so, with the understanding that there is still much work to be done.

In the process, it became apparent that string theory requires many dimensions and LQG requires exactly 4. The real evidence will come as we learn to test whether more dimensions can/do exist. It will ultimately go very far in proving one and equally disproving the other. Which one gets trumpeted and which gets trampled remains to be seen.
posted by mystyk at 10:37 AM on March 16, 2005


Scratch economics, then, and probably half of the social sciences

In fact, this is one of the damning criticisms of sociology and of (Freudian) psychology - that their "theories" were essentially untestable (although more a question of using generalities and loose terms, than of using mathematics so flexible as to be able to match any virtually any observed reality).

The underlying principle is still worth emphasizing: if a theory has worth, it is because it has implications (as the theory of relatively clearly did) that are (a) novel (as opposed to "predicting" only already known facts) and (b) therefore testable and (c) as Popper put it, therefore falsifiable. Such is science.

Intelligent design, as an an example of the opposite, makes no testable predictions, so it is not a "theory" in any sense that evolution, it's claimed opposite, is a truly a scientific theory.
posted by WestCoaster at 10:39 AM on March 16, 2005


It is not unique in the history of physics to propose a mathematical explanation for something seen, yet have that explanation require technologies beyond our current abilities to prove.

My hesitation when it comes to string theory is a nagging sense, as my entirely layman's ears listen to explanations, or as my entirely layman's eyes read explanations, that it's a theory which keeps changing not because reality and observation force it to adapt to what's true, but because they keep finding problems in the math, so they have to invent some mathematical construct to get from one part ot the theory to another.

Then they go off and try to decide what to tell people that new bit of math describes. I just get a little skeptical when it sounds like they start with the math, and then insist that the universe adhere to what their math says.
posted by theonetruebix at 10:48 AM on March 16, 2005


theonetruebixsays:
I just get a little skeptical when it sounds like they start with the math, and then insist that the universe adhere to what their math says.
Well, that is essentially what Einstein did. For example, Special Relativity's only reall assumption is that the fastest anything can travel is the speed of light which is constant. Everything else in SR is a consequence of the simplist mathematics required to make this somewhat consistant with classical space/time.
posted by MonkeySaltedNuts at 11:18 AM on March 16, 2005


Scratch economics

Economics is currently striving to become more scientific: books like this follow the formation of a physics model for economics.

There was a book out a few years ago, started by discussing Hobbes' Leviathan and moved into showing physics models being applied in social sciences, to model traffic, crowd control, economic systems...made a big splash, and I skimmed it, but I can't recall the title. Good book, though.
posted by NickDouglas at 11:44 AM on March 16, 2005


I linked to an anti-string-theory blog earlier; here's a pro-string-theory blog, to be fair (with a review of the same article). You'll come for the good science; you'll stay for complex, veiled smackdowns like this:

...what RB is saying about the black holes is otherwise equivalent to many random crackpots from Mass Ave who are only ignored because they have not gotten a Nobel prize for anything, not even for peace.
posted by Tlogmer at 12:02 PM on March 16, 2005


My hesitation when it comes to string theory is a nagging sense, as my entirely layman's ears listen to explanations, or as my entirely layman's eyes read explanations, that it's a theory which keeps changing not because reality and observation force it to adapt to what's true, but because they keep finding problems in the math, so they have to invent some mathematical construct to get from one part of the theory to another.

Right. When the evidence doesn't make sense, they just keep adding imaginary dimensions (that can't been seen or studied) until the theories are remotely possible.

I feel like they are mainly trying to sell a visual concept. Like atoms being imagined as round centers with electron satellites, they go to extraordinary lengths to explain why the true shape of the universe is the string.

The visual concept of an atom is just a convenience. String theory seems like a lot of daydreaming about models of convenience and very little actual science.
posted by DigDugDag at 12:10 PM on March 16, 2005


It is remarkable how tenaciously some people hold on to their faith in the notion that the world makes sense, even when the only basis for that faith-- a belief that the world has its source in some sort of intelligence-- has disappeared.
posted by koeselitz at 2:20 PM on March 16, 2005


No I was saying that since that average person probably can't be knowledgeable of a lot of the principles String Theory brings up, there are fewer people who could make an honest evaluation of the theory.

So, let's see. The average person cannot make an honest evaluation of the theory. However, you yourself are quite capable of making the evaluation that the theory is suspicious and probably wrong. Would you expect someone to listen to your opinion on brain surgery before going in for an operation?

It is remarkable how tenaciously some people hold on to their faith in the notion that the world makes sense, even when the only basis for that faith-- a belief that the world has its source in some sort of intelligence-- has disappeared.

Yes, the only way of explaining the world is through religious beliefs, and quite primitive ones at that. The explanations produced by the last few hundred years of scientific inquiry are of no practical value, so we might as well give up on that whole process.
posted by mcguirk at 4:26 PM on March 16, 2005


Old. News.

String Theory has been around for 2 (3?) decades now and hasn't been able to prove anything because we haven't been able to build a particle accelerator big enough to prove that the theories are sound. And in fact, each time we've proposed one big enough, the funding for it has been canceled.

At one point, people were concerned that a hydrogen bomb would ignite the Earth's atmosphere. I'm reminded of Dan Simmons' Hyperion Cantos and "The Big Mistake" when I hear rubbish of people complaining that "we might make a small black hole in an accelerator like that." Hogwash.

Build the big gigantic particle accelerator. Then test the theories. Then call me. Until then this is old news.

String theory is beautiful, it solves all the questions, and provides many answers. It is easy to confuse it with religion. We shall see what happens when the really big colliders are built.
posted by avriette at 5:16 PM on March 16, 2005


theonetruebix - I just get a little skeptical when it sounds like they start with the math, and then insist that the universe adhere to what their math says.

Except that you'd be remarkably surprised at how often that works. Antiparticles are a fine example - mathematics predicted these little fellas should exist and although many physicists were skeptical, claiming that it was "only math", they turned out to be real in the end.

In fact, it has seemed that historically math has been an excellent guide for physical theories. More often than not, bizarre outlandish purely mathematical predictions have turned out to have a remarkable amount of truth behind them.

I used to know quite a few better examples of this, but I'm drawing a complete blank right now.
posted by vernondalhart at 5:25 PM on March 16, 2005


Except that you'd be remarkably surprised at how often that works. Antiparticles are a fine example - mathematics predicted these little fellas should exist and although many physicists were skeptical, claiming that it was "only math", they turned out to be real in the end.

Isn't this just selective memory, though? Just off the top of my head, the minimal SU(5) Grand Unified Theories very elegantly wrapped up the electromagnetic, weak, and strong forces in a nice mathematical package, predicted a nice new piece of physics (proton decay), and turned out to be utterly wrong (hey! protons don't decay after all!)
posted by Johnny Assay at 6:01 PM on March 16, 2005


"Yes, the only way of explaining the world is through religious beliefs, and quite primitive ones at that. The explanations produced by the last few hundred years of scientific inquiry are of no practical value, so we might as well give up on that whole process."

To say that the world has its source in some sort of intelligence is not necessarily to be religious. Until a few years ago, nearly all philosophers and thinkers, religious or not, believed something like this.

The best example is Spinoza, who founded much of the current view; he, a forerunner to modern science if there ever was one, used the words "nature" and "god" interchangably. He wasn't, in my opinion, very "religious." In fact, he was also one of the first people to criticize the bible as self-contradictory.

Science attempts to understand the world; it must therefore assume beforehand that the world is comprehensible. What are the grounds of such an assumption? Either blind faith, or a knowledge, prior to observation, of the basis of the universe.
posted by koeselitz at 6:08 PM on March 16, 2005


What is this "prior to observation"? Prior to observation, there is no science, no faith, no knowledge, no universe.

We do seem to have observations, and we notice patterns in them, and from those patterns we can make predictions. But a pattern does not necessarily imply intelligence, unless you broaden the definition so widely that, e.g., a thermostat is intelligent.
posted by mcguirk at 6:36 PM on March 16, 2005


mcguirk: "What is this "prior to observation"? Prior to observation, there is no science, no faith, no knowledge, no universe."

Prior in logical order, not in temporal order. In short, if you choose to say "these are patterns, and continued observation of them will lead to further understanding/ability to predict outcomes," then you're judging beforehand that patterns are the fabric of the universe.

That's all I mean. You say we "notice patterns" in observation; but it's only the assumption that such patterns are really patterns, and not random flukes, that leads us to keep observing and keep testing. When we do science, we assume that the world is rational; we assume that the world will be mathematical in some way, for example, and that it's only our application of mathematics that's wrong.

Hume (and a lot of other people) asked: how do we know that the principle of cause and effect always holds? Most of us have no idea-- at least I don't, and am forced to assume that, when things happen, there are causes that I can understand.

Up until a few years ago, people had taken to calling the intelligence-- well, "rationality" or "reasonableness" are probably better terms-- of the world "nature." They said that there were laws, and that, once we understood all of these laws which governed the world, we would be masters of nature. That, at least, seemed to be the goal of the modern scientific project founded by Bacon.
posted by koeselitz at 7:03 PM on March 16, 2005


OK. But most scientists acknowledge that as well, I think. We could be mistaken, and the predictions we call "the known laws of physics" should really be "the known laws of physics, except that everything will degenerate into complete chaos one second from now and nothing will be comprehensible or predictable."

But we seem to find that operating from the former position is more useful. I don't see how your argument can be a criticism of string theory. Pursuing string theory is just as reasonable as, say, buying groceries for next week. Sure, the known universe could unravel by then, but I'll still buy the groceries.
posted by mcguirk at 7:22 PM on March 16, 2005


For laymen wanting answers on string theory, try SuperStringTheory and The Elegant Universe.
posted by Gyan at 7:24 PM on March 16, 2005


So, let's see. The average person cannot make an honest evaluation of the theory. However, you yourself are quite capable of making the evaluation that the theory is suspicious and probably wrong. Would you expect someone to listen to your opinion on brain surgery before going in for an operation?

I didn't say it was probably wrong, I said it could not be proved. In the context of my point, yes I would be equally suspicious of someone's theory for a substitute for brain surgery that could yield no provable results, or simply could not be proved to be ineffective.

TOE theorists don't lose a patient to a brain tumor if they are wrong. In fact, all they have to do is ensure that they can never be proved wrong and their studies are safe. String Theory remains, in this respect, right on track!

Since you're casting aspersion on my important opinions regarding brain surgery: Several years ago the medical establishment thought a certain form of brain surgery was perfectly acceptable for certain patients. The surgery was called a lobotomy. People who influence opinions in the scientific community are not infallible.
posted by DigDugDag at 7:39 PM on March 16, 2005


TOE theorists don't lose a patient to a brain tumor if they are wrong.

No. There's much more at stake than that. A valid theory of physics leads to massive consequences, both good and bad, for the entire human race. You could just as easily have said, "All that crazy nonsense that Bohr is spewing about 'wave functions' has nothing to do with everyday reality. It makes no practical predictions." But then people tend to come along and find that you can use it to build things like atomic bombs, computers, fiber optics, MRI machines, etc.

I didn't say it was probably wrong, I said it could not be proved.

I think you are making the same mistake as the quote from the blog guy. There's a big difference between "makes no predictions", and "makes no predictions that can be conveniently tested right now".

Should we abandon theoretical science whenever its predictions become "really expensive" to test? Even though the benefits of every previous discovery have vastly outweighed the cost of the research? (Of course there are many negative consequences as well, but we can leave "is progress bad?" for a separate debate.)

In fact, all they have to do is ensure that they can never be proved wrong and their studies are safe.

Do you believe their conscious intent is to manipulate the theory so it becomes permanently untestable? That sounds pretty paranoid.

People who influence opinions in the scientific community are not infallible.

No, they're not, and they should be subject to criticism. And even the least-informed critic could happen to be right. So I guess I should say, God bless those who have the audacity to attack both the motives and the results of people who have not only devoted their entire lives to the subject, but are intellectually pretty much geniuses, while coming from a position of almost complete cluelessness. Even if it seems a little annoying from where I'm sitting.
posted by mcguirk at 8:41 PM on March 16, 2005


Wow, I'm really amazed at all the antipathy twoards string theory on this board. It's just bizzare. I'm willing to bet that not a single one of you understands the math (and if you don't understand the math, then you don't understand the theory) and yet you blast it.

I'm simply not in a position to analyze the evidence directly, but the idea that the worlds leading physisits have lost their minds is a bit hard to swallow.
posted by delmoi at 9:28 PM on March 16, 2005


delmoi - I'm in roughly the same boat as you here. I've seen too many of my fellow students in my physics classes blindly jump on one bandwagon or another (usually pro-string theory) without having the foggiest idea what it actually means.

Johnny Assay - As for the SU(5) predicting proton decay, I though that issue hadn't really been settled yet. IIRC, it predicts that protons will decay, just incredibly slowly, to the point where they become nearly completely inobservable. So unless there's something I'm missing here, you can't justifiably say that that was proven wrong, just that it hasn't been proven right.
posted by vernondalhart at 10:35 PM on March 16, 2005


How in the world are they supposed to make observation on the scale of a Plank length..or smaller?

"TOE theorists don't lose a patient to a brain tumor if they are wrong."

No. There's much more at stake than that. A valid theory of physics leads to massive consequences, both good and bad, for the entire human race.


You don't understand my point. My point is that a brain surgeon would have a definite moment of failure (losing the patient). Theoretical scientists don't always have that moment.

String theory is a bandaid!
posted by DigDugDag at 10:01 AM on March 17, 2005


How in the world are they supposed to make observation on the scale of a Plank length..or smaller?

They will probably test some indirect prediction of the theory, as indeed already seems to be possible within the next few years according to some of the information here. Forgive me if the fact that you find it difficult to imagine does not strike me as strong evidence that it is impossible.

Theoretical scientists don't always have that moment.

You mean they don't have that moment in a way that is as conveniently and immediately accessible as you require.

String theory is a bandaid!

I suppose when we are reduced to shouting slogans, we must admit that the discussion should have ended long before.
posted by mcguirk at 11:04 AM on March 17, 2005


Or when you reduce my posts to selective quotes, that might be a good time to come to the same realization. My comments about dying from a brain tumor were in response to your own comparison to brain surgery. I didn't require the "oh no the patient has died" moment, I used it to explain why your analogy to brain surgeons does not apply.

I said before that String Theory seems more like a perceptual change of subatomic structure (the "round" subatomic particle versus the string) with a lot of dimensions added on to make the idea work. In this respect it seems like a bandaid. Why is there so much talk of "elegance" and other subjective ideas when the frontmen of Stirng Theory talk?

Every response you've made to my quotes misinterprets what I say somehow. I don't think you are interested in talking about this, but instead you seem more interested in being "right".

Good thing I can wait on these indirect tests of indirect effects of [something] to prove my own opinions wrong.
posted by DigDugDag at 1:22 PM on March 17, 2005


I think the elegance of string theory arises from its seeming simplicity - Particle physics has gotten just a little too complicated lately, and some sort of reduction would be nice. I mean, we went from 100+ atoms to two subatomic particles, the proton and the electron.

And now all of a sudden we have 36 different quarks (including color and antiquarks), 12 leptons and at least 5 mediators, last I checked. If these were all simply different "vibrational modes" of a single entity, say a string, it would be really quite nice.
posted by vernondalhart at 2:15 PM on March 17, 2005


I don't think you are interested in talking about this

You're right. (And there's another selective quote.) Good luck to you.
posted by mcguirk at 3:46 PM on March 17, 2005


I said before that String Theory seems more like a perceptual change of subatomic structure (the "round" subatomic particle versus the string) with a lot of dimensions added on to make the idea work. In this respect it seems like a bandaid.

No, the extra dimensions are fundamental to string theory, not incidental. Changing the small-scale shape of the universe gets rid of the problems associated with geometric point particles in traditional efforts to combine relativity and quantum mechanics.
posted by Tlogmer at 4:35 PM on March 17, 2005


delmoi said " Wow, I'm really amazed at all the antipathy twoards string theory on this board. It's just bizzare."

raaka's original post associated string theory with creationism and it snowballed from there. Welcome to metafilter.
posted by Tlogmer at 4:39 PM on March 17, 2005


People shouldn't give up on string theory and people shouldn't explore other options either. Theoretical physics and math should be pushed as far as it can. Whether theory ever runs into practice and experimentation is moot although we seem to expect the collision.
posted by GeorgeHernandez at 11:38 AM on April 7, 2005


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