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Is String Theory Really a Scientific Theory?
vk38 writes, "The New Yorker is running a story on whether String Theory is really a scientific theory or just an abstract exercise in math designed to churn out papers and Ph.Ds for the established academics. The article reviews two current books, by Lee Smolin and Peter Woit, laying out the case against string theory."
From the article: "Dozens of string-theory conferences have been held, hundreds of new Ph.D.s have been minted, and thousands of papers have been written. Yet... not a single new testable prediction has been made, not a single theoretical puzzle has been solved. In fact, there is no theory so far — just a set of hunches and calculations suggesting that a theory might exist. And, even if it does, this theory will come in such a bewildering number of versions that it will be of no practical use: a Theory of Nothing... String theory has always had a few vocal skeptics... Sheldon Glashow, who won a Nobel Prize for making one of the last great advances in physics before the beginning of the string-theory era, has likened string theory to a 'new version of medieval theology,' and campaigned to keep string theorists out of his own department at Harvard. (He failed.)"
String theory is a scientific theory that has neither been proved nor disproved to my knowledge.
I could speculate all day on whether or not it is fact but from what I've read, I will make a few statements. It seems that string theory was invented to satisfy some things we could not explain. This doesn't mean it's wrong or right although some people will contend that it is most probably wrong.
As the summary points out, few (if any) of String Theory's propositions can be tested or even observed. So it is simply an unknown right now. We cannot measure the proposed strings so how can we prove if they exist or they don't? We simply can't yet.
A good analogy would be Bohr's early assumptions about the atom. They were wrong but they were a step in the right direction. In hindsight, we see this now but we don't know what the future holds for String Theory. I'm just glad there are people out there thinking outside the box.
Do not fret, however, as scientists have been very resourceful at proving/disproving theories. I submit, for example, the exercise of determining the diameter of the building blocks of matter. Scientists had the idea to fill up one cubic milliletre of oil and dump it on top of a trough of water with a roller across the top. As the oil spread out, they moved the roller further down the trough. Once they started to see non-reflective parts of the water, they moved it back until they agreed the oil was completely spread out to the best of their abilities. Using this area, they determined how thick a molecule of oil could be without precision tools!
Similar ingenious tests have been devised to easily find the diameter of the earth at sunset on a beach with a yard stick or ruler.
So even though we may never be able to measure these strings, there are still some options left to explore to record properties that may prove/disprove their existence. We're merely in the very early stages of the scientific process.
Let us be excited about String Theory, even if it is wrong it sure is interesting. Nothing's wrong with a scientist who dreams, is there?
My work here is dung.
String theory sounds weak. Let's upgrade the name so it sounds like it has to be true. Henceforth it will be referred to as String Fact.
I'll even throw a bone to an entrepreneural slashdotter out there. STRINGFACT.COM is not registered yet. It is yours for the taking.
Ninjas don't carry tic tacs
So which is it: the best of times or the worst of times?
According to Schrodinger, both.
Finkployd
Short Answer: No.
Long Answer: Yes.
Longer Answer: Both of the above, but each in a separate Universe.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
There's a difference between what's not practically testable and what's truly unfalsifiable. As long as it's conceptually possible to come up with a falsifying experiment, even if it's wildly impractical, it's still a scientific theory. We may yet come up with ways to test the theory. Sometimes that's because somebody comes up with a clever new test, an ingenious new reformulation of the theory, receives unexpected results from an exsting accelerator, or builds a new particle accelerator.
What's happening here is that people are complaining that the scientific establishment has made it difficult to work in alternatives to string theory. But just because you can't get a job to disprove a theory doesn't make it unfalsifiable. There needs to be healthy debate in the scientific community about which theories to work on. Shutting valid theories down is not healthy for science, but neither are accusations that conflate "impractical" with "impossible".
Let the physicists, who are the only people who can truly understand this, sort it out. They likely don't need the academic process becoming any more politicized than it already it. If it's a blind alley, they'll find that out in due time. While it's regrettable that it's taking as long as it is to reach a conclusion on the issue, come on - it ain't exactly flippin' burgers, and we're not exactly hung up waiting for the result. Let the scientists work.
there is no need to sign your posts. this isn't usenet. your username is right there above your post. stop it.
String theory is at times one of the biggest con jobs in Physics, and at other times some of the most interesting speculation. It's also the 'Theory that will NOT die!' reminding me of so many late night C rate thrillers.
Why? Because everytime string theory gets disproven, they come out with a new theory and call it 'String Theory'. String Theory from the 70's really doesn't resemble current string theory much other than the name. It's strange that this is so, but there are a lot more politics involved than there is science at times. And the author is right, there are lots of articles being written, but not much going on that can be said to prove the theory, and little in the way of predictions (cause those could be tested). And so far, everytime someone does stand up and make predictions, it quickly gets disproven by actual tests. Which may be why no one is predicting much using it anymore.
At this point actually String Theory may very well be the most 'disproven' theory in physics. But that doesn't seem to stop people from trying. It will be curious to see what science has to say about all of this 50 years from now. To be honest I think many of us have gotten too close to the subject to be objective about it, and I think that is not helping the issue on either side.
Having a "rolled up" dimension doesn't require an extra dimension, because they're not _actually_ rolled up. The metric used to describe them is just easy to picture that way. Just like curved 4-dimensional space time doesn't need a 5th dimension to be curved into. I tried looking for a good web-site that explains this, but didn't find one in the time I'm willing to spend looking for one. I'm sure someone else knows of one, though.
Ben Hocking
Need a professional organizer?
String theory might not have earned the rights to be called a theory yet, but as with Bohr's model of the atom, perhaps we could agree that it has earned the right to be called a model.
Ben Hocking
Need a professional organizer?
You, sir, have no idea what Philosophy is.
Do you "prove" logic by testing it, or testing anything is to apply logic to the issue?
When something "becomes" science, that's because it never was philosophy. Philosophy is that discipline that provides you the tools with which you build science. Not the other way around.
Conservatism: (n.) love of the existing evils. Liberalism: (n.) desire to substitute new evils for the existing ones.
it's true, it really is FUD.
String theory hasn't been replaced by newer versions, it's been updated with small modifications like "what if the basic premise is the same, but instead of a 1D string vibrating in 4 dimensions (x,y,z and t) it's vibrating in 11 dimensions, where the other dimensions are curled up within the planck length?"
There are reasons why string theory has failed to come up with any NEW predictions. For one thing, it's being constantly tweaked so that it is consistent with EXISTING experimentation. After all, why would you build a theory that you hope will become a GUT if it's not consistent with other proven theories?
The other thing is that this is a theory... the fact that it (mathematically) treats particles as being a 1D string vibrating in n-dimensions doesn't actually mean that if you could see items smaller than the planck length, that you would actually see a vibrating string!! It's a mathematical representation... the math doesn't have to represent exactly what's happening as long as it can be used to describe what is happening.
After all, modern chemistry is incredibly useful for predicting how atoms interact with eachother to form compounds... even though it's based off the idea that electrons orbit a nucleus like a tiny little planet orbitting a sun... that is precisely NOT what an electron does, but who cares, the math allows you to make determinations. It's the same with string theory.
I do not think that string theory is a con job. I do, however, think that attempting to come up with a GUT is a MUCH MUCH larger task than simply trying to explain, say, quantum behaviour, like tunneling.
They're starting with a very simple, and very elegant premise (that all particles are periodic vibrations with different frequencies corresponding to different particles) and then building from there. Hell... start with that and just try and figure out how to represent the periodic table... that alone would be mind-boggling. Now start trying to figure out what particle interaction would look like... then build up from there. The trick, is that it's possible to describe nearly everything using this theory... but it hasn't happened yet. Just because it's possible doesn't mean it'll be easy.
This, of course, probably means that it's the wrong way of going about it... but that doesn't make it a waste of time... the hardest part, I think, will be in having enough patience to see what the theory can produce outside of existing theories... unfortunately it has to be harmonized with existing theory ;-)
Oh god, that woman is John Romero!
Of course String Theory makes testable predictions. Just like General Relativity and Quantum Mechanics make testable predictions.
The bad news is that they are the same predictions that General Relativity and Quantum Mechanics make, many of which we've already tested, and is thus indistinguishable from them.
The good news is that String theory makes the same predictions as GR and QM while still being only one theory.
It is the non-compatability of GR and QM that creates the need for something like ST. If ST doesn't make a single unique prediction, but is able to explain both the quantum and relativistic worlds, then not only is that a theory, it's a great theory.
The enemies of Democracy are
I am a geek, but I have seriously problems with math ability. I have a Bachelor of Arts degree.
;)
Sorry to break it to you, but you're a hippie, not a geek.
Developers: We can use your help.
Here's the problem though. GR and QM are both, relative to ST, extremely simple. And while ST may make the same predictions that GR and QM make, it does so in a far more complex way, without adding any extra information -- QM and GR are incompatible, but ST fails to resolve those incompatibilities in a testable way.
GR was more complex than Classical Newtonian Mechanics, but it was, essentially, a value-added theory: it explained a bunch of things that Classical Mechanics couldn't, all while remaining compatible with Classical Mechanics in places where Classical Mechanics made accurate predictions. Therefore, GR was taken to replace classical mechanics, despite the added complexity of the theory, because it was broader in scope, falsifiable, and provably more correct than the theory it replaced.
ST does not fit this mold. It is far, far, far, far more complex than either GR or QM, and makes no extra falsifiable predictions. It doesn't resolve the inconsistencies between the two. In other words, from a purely scientific perspective, it's just a hypothesis and not a particularly useful one at that.
Of course, I'm a mathematician by training and lots of interesting math has come out of ST, so for that I'm happy.
"Sterile" neutrinos, Supersymmetric particles, Kaluza-Klein particles, Energy 'leaking' into higher dimensions...
These are some of the predictions of string theories.
And they all can, to some degree, be tested empirically.
All the technology that needs to be implemented to do this isn't readily available right now, but hopefully, in coming years with experiments such as LHC and IceCube coming online, we could start to see meaningful results - Remember, it took years for empirical confirmation of General Relativity, simply due to technical limitations.
First of all it is no surprise that it resembles QM because it is QM. It assumes QM and applies it to a vibrating string, brane, etc.. But there is no new theory because there's at least a handful of different ways to do this and they're all called string theory. GR on the other hand is not as obvious. They are able to get equations that resemble Einstein's equations, but GR does NOT just pop out of it.
I love it how this happens; whenever there is a discussion about whether something is or is not a theory, or isn't actually science, the Science People always piss of the Philosophy Poeple because philosophy always gets used as a dumping ground for everything that starts out with "what if..." but doesn't quality as science. "Damn it guys, we have rules too, you know. Stop sending us your trash!"
I read Smolen's book recently, and learned a lot of new and interesting things about string theory from it. Some problems with string theory:
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This is why you don't get it: That is behaviour which is generally considered unscientific. If you need to keep modifying your theory to explain stuff, then it's not a scientific theory. It's an ad-hoc mess of empiricism of zero real value. The rules of the game are:
1) It must be testable (falsifiable)
2) You must provide new predictions
3) You must explain previous observations, observations not used in formulating the theory., and ideally, none at all.
4) You must do so using fewer postulates (assumptions) than the previous theory.
The word you're looking for is "model". But how is this another thing? Our current understanding is a model as well. The question is whether it's a better model or not is still there and unanswered.
You have no clue. Modern chemistry is not based on any such model. It's based entirely on the standard model of physics. There is not one, not one! molecular property that can be described in anything less than a fully quantum-mechanical treatment. All of chemistry is purely due to quantum-mechanical effects.
And string theory is not the same at all, even if you'd been right. String theory is an attempt at a more basic and general theory of quantum mechanics, in the same way as classical mechanics is a limiting case of quantum theory. It is not an approximation of quantum theory, and not intended to be one.
You don't get it. The periodic table is already entirely explained from QM, and has been for some time. There's no more reason to describe it in terms of string theory than to describe the motion of billiard balls in terms of quantum mechanics: It's unnecessary because it's already explained by classical mech, and we know classical mech is a subset of quantum mech.
In the case of string theory, all they need to do is show that QM is a subset of that theory. That's not hard and it is. It forms the basic premise of their work as well as the goal. The idea is that they're going to work from part of quantum theory and relativity and somehow arrive at the whole thing. Which parts the