Is string theory really science?

[kochanskij]

The scientific method says that if experiments or observations falsify a theory, that theory must be rejected.
String theory requires space to have 9 dimensions. But observation shows that our space has only 3 dimensions. This alone should falsify string theory.

I know that scientists have amended an ad-hoc hypothesis that 6 of the dimensions are curled up too tiny to observe. But there is no experimental evidence of this. And the theory does not predict or explain why 3 dimensions should be large and 6 tiny.

If you add enough ad-hoc hypotheses, any theory could be accepted. The Earth-centered universe could still be believed if you add enough epicycles and other unsupported ideas to explain the motion of the planets. But science usually rejects this kind of fixing up of a theory (mainly due to Occam's Razor). So, without ad-hoc hypotheses, shouldn't string theory also be rejected?

Does any future experiment even have the potential to falsify string theory? If so, what might that experiement be? If not, then string theory is not science. It is a religion.

 

[Dickfore]

The scientific method says that if experiments or observations falsify a theory, that theory must be rejected.
String theory requires space to have 9 dimensions. But observation shows that our space has only 3 dimensions. This alone should falsify string theory.

Please show what observation shows that space has 3 dimensions.

I know that scientists have amended an ad-hoc hypothesis that 6 of the dimensions are curled up too tiny to observe. But there is no experimental evidence of this. And the theory does not predict or explain why 3 dimensions should be large and 6 tiny.

Is there any experimental evidence against it?

If you add enough ad-hoc hypotheses, any theory could be accepted. The Earth-centered universe could still be believed if you add enough epicycles and other unsupported ideas to explain the motion of the planets.

Please show your work. Where can I find a refernce to such a theory. Does it still predict the correct positions of celestial bodies, even the ones that were unknown in antiquity?

But science usually rejects this kind of fixing up of a theory (mainly due to Occam's Razor). So, without ad-hoc hypotheses, shouldn't string theory also be rejected?

Occam's Razor is not part of the scientific method.

Does any future experiment even have the potential to falsify string theory? If so, what might that experiement be? If not, then string theory is not science. It is a religion.

Maybe. I don't know that much string theory.

 

[yenchin]

Does any future experiment even have the potential to falsify string theory? If so, what might that experiement be? If not, then string theory is not science. It is a religion.

In principle, yes, but it's observation instead of experiments [at least for now]. Stringy effects at high energy could have contributed in the very early universe, and with the expansion of the universe even tiny effects can be magnified. In the current non-stringy standard cosmology, you can use quantum field theory to study what is the effect of quantum fluctuation to matter perturbation, and this is basically the seeds that later form galaxies. In certain models of string theory, stringy effects will modify this, and cosmological observations can in principle falsify some of these models.There may also be imprints on the cosmic microwave background that differ from non-stringy models [http://arxiv.org/abs/0704.0647v1] . Of course all these are works and ideas in progress, but in principle they can falsify or at least put some constraints on string theory.

See also http://www.math.columbia.edu/~woit/testable.pdf.

 

[haushofer]

I think string theory should be regarded as a framework or paradigm, not as a single theory (alas the name!). In that sense it could be compared to quantum field theory, which is also a paradigm. A better name for String Theory would perhaps be "string paradigm".

In that sense you can wonder what it means to "falsify string theory". You should be able to falsify specific theories in the string paradigm, but to falsify the paradigm itself would be very hard. How would one for instance "falsify the framework of quantum fields"?

 

[haushofer]

The scientific method says that if experiments or observations falsify a theory, that theory must be rejected.
String theory requires space to have 9 dimensions. But observation shows that our space has only 3 dimensions. This alone should falsify string theory.

For centuries, observation had shown that time is absolute, that nature is continuous, that the universe is static, that continents don't drift, etc. etc. Physics showed us how to go beyond intuition, and showed us that the contraries of all these statements are actually true.

Why would space be 3-dimensional? Because we accidentally, as humans, live at energy scales at which it seems 3-dimensional?

Don't get me wrong: I don't know how many dimensions space has. I only know that ST is a promising candidate for quantum gravity and a very interesting playground for physics beyond the standard model. ST is very conservative; you extend the notion of point particles and just apply all the lessons learned in the last century. This conservative route turns out to have "fancy" consequences.

I know that scientists have amended an ad-hoc hypothesis...

It's not ad-hoc. It is required by the theory, as we understand it.

If you add enough ad-hoc hypotheses, any theory could be accepted. The Earth-centered universe could still be believed if you add enough epicycles and other unsupported ideas to explain the motion of the planets.

Could you show such a model which can describe all phenomena described by modern cosmology?

Does any future experiment even have the potential to falsify string theory? If so, what might that experiement be? If not, then string theory is not science. It is a religion.

See my post one up.

 

[kochanskij]

First, to answer your question. The earth-centered universe is an idea proposed by Ptolemy that the planets revolve on small circles centered on other circles (epicycles) around earth. Later, it was proven that the paths of all planets and comets (any path at all) could be reconstructed from a large finite number of epicycles. This is similar to Fourier analysis recontructing any function from sin and cos waves. One reason science doesn't believe this theory anymore is that it is too complicated and has too many hypotheses. Newton's law of gravity and motion is much simpler.

String theory also adds too many ad-hoc hypothesis. Strings require 9 space dimensions but we see only 3, so scientists propose that 6 are curled up tiny. This may be true, but the theory doesn't require this curling up and there is no evidence for it. Now some people have proposed that all 9 dimensions are large but we are stuck to a 3-D membrane. So which is it? String theory doesn't say. Strings predict many new particles that haven't been found, so scientists propose that they must have huge masses. This may be true, but the theory doesn't require large masses and there is no experimental evidence for them. There seems to be too many "unsupported speculations" being made just to try to save the theory.

I agree with Haushofer in that string theory/M theory is a paradigm, or philosophy. It is not a specific fundamental theory. We can not prove or falsify a paradigm. Physicists must develop one definite specific string theory that can be tested by experiments/observations.
I also agree with Yenchin that observations of cosmic background radiation might test string theory. But, we still need some definite prediction from the theory to test it.

I know that many weird ideas in science have turned out to be true. But these have been confirmed by experiments/observations before scientists accepted them. String theorists seem to be saying "just believe all these weird things because we say so". That is not the method of science; that is the method of religion.

 

[Nabeshin]

First, to answer your question. The earth-centered universe is an idea proposed by Ptolemy that the planets revolve on small circles centered on other circles (epicycles) around earth. Later, it was proven that the paths of all planets and comets (any path at all) could be reconstructed from a large finite number of epicycles. This is similar to Fourier analysis recontructing any function from sin and cos waves. One reason science doesn't believe this theory anymore is that it is too complicated and has too many hypotheses. Newton's law of gravity and motion is much simpler.

String theory also adds too many ad-hoc hypothesis. Strings require 9 space dimensions but we see only 3, so scientists propose that 6 are curled up tiny. This may be true, but the theory doesn't require this curling up and there is no evidence for it. Now some people have proposed that all 9 dimensions are large but we are stuck to a 3-D membrane. So which is it? String theory doesn't say. Strings predict many new particles that haven't been found, so scientists propose that they must have huge masses. This may be true, but the theory doesn't require large masses and there is no experimental evidence for them. There seems to be too many "unsupported speculations" being made just to try to save the theory.

I agree with Haushofer in that string theory/M theory is a paradigm, or philosophy. It is not a specific fundamental theory. We can not prove or falsify a paradigm. Physicists must develop one definite specific string theory that can be tested by experiments/observations.
I also agree with Yenchin that observations of cosmic background radiation might test string theory. But, we still need some definite prediction from the theory to test it.

I know that many weird ideas in science have turned out to be true. But these have been confirmed by experiments/observations before scientists accepted them. String theorists seem to be saying "just believe all these weird things because we say so". That is not the method of science; that is the method of religion.

String theory is indeed a framework, but I think it's still subject to falsification. In principle at least, one could derive some sort of general result from the framework of ST which simply is inconsistent with our known universe, falsifying the whole thing. Much more likely, however, is that we rule out large swaths of string theories from observation.

Also, the fact that spacetime is 11 dimensional is not in the slightest a hypothesis, but rather a PREDICTION from the theory itself. This is rather startling, because I know of no other theory which actually predicts the dimensionality of spacetime (correctly or otherwise). It would certainly be fantastic if we could show that, in general, things compactify to a universe resembling ours, but this is of course a tall order. I think the analogy to QFT is really good here -- we can imagine tons of QFTs, like people are doing right now with compactifications of string theory, and simply hope to find ones that are either 1) interesting, 2) similar to our universe, or 3) falsifiable.

I'm really surprised that you don't like string theory and find it arbitrary, given that the Standard Model is perhaps one of the most ad-hoc theories I can think of. Sure, it has great predictive power, but we had to put a lot into it (masses and particle content!) to get this power out. String theory, on the other hand, requires one (dimensionful!) parameter: the string length. Now, it would certainly be nice if the theory could, from that, predict the dynamics of its dimensions to reveal 3 macroscopic dimensions like we see, and perhaps it can, but the jury's still out.

Main motivations for scientists believing so strongly in the validity of string theory despite its lack of experimental validation are obviously deeply theoretical. But such concerns led to Einstein developing GR, it's just that with that case, predictions were much easier to make and falsify. I think it's way too soon to get on either side of the bandwagon though, and I very much dislike it when popularizers of science like Greene make it sound as if we KNOW ST is correct. I don't think anyone is saying 'just believe this because we say so', so much as, 'look at all these amazing things within string theory, what are the odds that this theory is wrong and still contains all of this?'

 

[tom.stoer]

Let me add one remark regarding the relation of QFTs like the SM and string theory.

QFTs, mostly (partially supersymmetric) gauge theories can be constructed for different interactions but always w/o gravity. The construction is well-understood, but the question which specific symmetry structure you want to use is ad hoc. I would say that it's common believe that interactions w/o gravity have to be described using gauge theories.

Taking gravity into account the situation becomes much more complicated. It could be that there is a similar construction principle call supergravity (SUGRA) which is much more restrictive regarding matter content, interactions and dimensionality of spacetime.

The big difference between gauge theories and SUGRA is renormalizibility. For gauge theories we know (infinitly) many cancidates which are perturbatively renormalizable. For SUGRA it's not yet clear, but perhaps there is not even one!

No look at strings: what the string theory framework essentially does is to convert a large class of supergravity-gauge-theories which have been constructed ad hioc into vacuum solutions of one underlying theory

 

[tom.stoer]

Let me add one remark regarding the relation of QFTs like the SM and string theory.

QFTs, mostly (partially supersymmetric) gauge theories can be constructed for different interactions but always w/o gravity. The construction is well-understood, but the question which specific symmetry structure you want to use is ad hoc. I would say that it's common believe that interactions w/o gravity have to be described using gauge theories.

Taking gravity into account the situation becomes much more complicated. It could be that there is a similar construction principle call supergravity (SUGRA) which is much more restrictive regarding matter content, interactions and dimensionality of spacetime.

The big difference between gauge theories and SUGRA is renormalizibility. For gauge theories we know (infinitly) many cancidates which are perturbatively renormalizable. For SUGRA it's not yet clear, but perhaps there is not even one!

No look at strings: what the string theory framework essentially does is to convert a large class of supergravity-gauge-theories which have been constructed ad hioc into vacuum solutions of one underlying theory

 

[tom.stoer]

Let me add one remark regarding the relation of QFTs like the SM and string theory.

1) QFTs, mostly (partially supersymmetric) gauge theories can be constructed for different interactions but always w/o gravity. The construction is well-understood, but the question which specific symmetry structure you want to use is ad hoc.

I would say that it's common believe that interactions w/o gravity have to be described using gauge theories.

2) Taking gravity into account the situation becomes much more complicated. It could be that there is a similar construction principle call supergravity (SUGRA) which is much more restrictive regarding matter content, interactions and dimensionality of spacetime.

The big difference between gauge theories and SUGRA is renormalizibility. For gauge theories we know (infinitly) many cancidates which are perturbatively renormalizable. For SUGRA it's not yet clear, but perhaps there is not even one!

I would say that it's widely believed that the low-energy sector of interactions w/ gravity taken into account have to be described using SUGRA-gauge theories.

3) Now look at strings: what the string theory framework essentially does is to convert a large class of supergravity-gauge-theories (which have been constructed ad hoc) into vacuum solutions of one underlying theory! In addition another large class of theories (infinitly many) which could be constructed ad hoc is ruled out b/c they cannot be derived from string theory. I bet that you cannot derive a world with gravity but w/o other fundamental forces; neither can you derive a theory like the SM in flat Minkowski spacetime w/o gravity. Therfeore string theory turns a construction principle into solutions.

It's like having infinitly many low-energy theories describing water, iron, ice, wood, ... and then you discover QED. QED does not predict whether we observe water or ice, but it provides a unique framework from which all these different states of matter van be derived in principle.

I would say that many string theorists believe that this is one cenmtral feature of the string paradigm. Somehow the theory looses predictive power b/c it cannot tell you which low-energy theory you will observe, but it does explain which theories can exist in principle.

 

[Hobin]

I think the word 'theory' is a misnomer. It suggest a scientific grounding in solid evidence, which string theory lacks. Absolutely, there are many good reasons to assume that string theory will ultimately prove to be correct, but as of yet, there is no such experimental proof. There is only 'well, everything seems to fit if we use it'. That's not a bad thing, but, like I said, I would rather we not use the word theory to describe it.

(I mean, can we really blame the creationists for saying evolution is 'just a theory' when we use the word theory for pretty much everything ourselves?)

 

[nicoo]

I rather share kochanskij's point of view. strings are not what we'd expect from a ToE. it needs too many hypothesys and makes no enough testable predictions.

Hypothesys:
- 11 dim
- calabi-yau (why calabi-yau and not something else?)
- susy (+ hundreds of free paramaters)
- particules are strings
- 100^500 theories

All of this do not even make possible to derive the standart model in its full details (+ possible extenions). All we have are models looking more of less like the SM.

In the contrary, a good theory should decreased the free parameters (if you believe in science and not in landscape)
Maybe one day a principle will be found to make strings able to single out a testable theory, I hope so. But since 20 years is has not be the case.

SM was constructed based on experience. Free paramters need to be fixed experimentally but it made thousands of testable predictions. It is a terrificly efficient theory. That what we ask to Strings, predictions must be at least as great as hypothesys are.

 

[haushofer]

All of this do not even make possible to derive the standart model in its full details (+ possible extenions).

But how much of a breakthrough would it be if it would be shown that ST could "reproduce the standard model"? ST lies way, way, way beyond the energy scales of the standard model. What would we really learn if we could explicitly derive the SM from ST, besides that it is then explicitly shown to be possible?

 

[nicoo]

Deriving SM would be a breakthrough, but it is the strict minimum we can ask to a ToE.
If a theory aiming to be a ToE is not able to explain what we already know to be true, then the theory is manifestly wrong or at least incomplete. I would say ST is still incomplete in that sense.

To come back to the question of this thread: Does it mean ST is not science ?
I don't think so, IMO it is an incomplete and untestable theory for the moment. Maybe one day it will proved to contain the SM and we could call it a "possible true" theory, but it is not case...

I find much more promising and efficient for instance NCG which lives at Planck scale too but does derive the full SM + Gravity and makes predictions + postdictions (mass of the top...)
Predicted Higgs mass was already ruled-out, but it might be fixed if new particules are discovered at the LHC. No Landscape problem, not 10 dimensions with Calabi-Yau... and the SM + Gravity fully derived.

 

[tom.stoer]

Can anybody derive solid state physics from QCD + QED?

 

[PAllen]

Can anybody derive solid state physics from QCD + QED?

Isn't that one of the odd numbered exercises in Physics 253?

 

[CaptFirePanda]

I would have to say that, at this point, calling it a theory is a misnomer. Does this make a huge difference to anything? No.

 

[John232]

I think string theory is more of a mathimatical trick than science. The goal being to uncover underlying possiblities in physics to give a clue or solution to unexplained phenomena in physics. In doing this, it has failed. All it has shown us is that physics can be explained in about any number of dimensions and could be equally valid. I think this is a result of mathematics itself and not physics. All we have found is that physics can work the same way in about any number of dimensions mathmatically. It is too complex to be logically changed in a logical way that would in turn describe our world more accurately, so then there would never be any reason to assume that reality has to be made up of more or less dimensions. Even if it was, it could still probably be described just as accurately in four dimensions because the mathimatics could allow that to happen. So, then there would never be a reason to think the universe should have a certain amount of dimensions, since mathematics allows any number of dimensions to be descibed with a different number of dimensions equally.

 

[PAllen]

I think string theory is more of a mathimatical trick than science. The goal being to uncover underlying possiblities in physics to give a clue or solution to unexplained phenomena in physics. In doing this, it has failed. All it has shown us is that physics can be explained in about any number of dimensions and could be equally valid. I think this is a result of mathematics itself and not physics. All we have found is that physics can work the same way in about any number of dimensions mathmatically. It is too complex to be logically changed in a logical way that would in turn describe our world more accurately, so then there would never be any reason to assume that reality has to be made up of more or less dimensions. Even if it was, it could still probably be described just as accurately in four dimensions because the mathimatics could allow that to happen. So, then there would never be a reason to think the universe should have a certain amount of dimensions, since mathematics allows any number of dimensions to be descibed with a different number of dimensions equally.

This is just false. Various numbers of dimension are not 'put into string theory'. Instead, the number of dimensions comes out as prediction of the string framework, and there is only one choice for the most general framework: 11. In principle, this is a falsifiable prediction. Unfortunately, for now, it is not a testable prediction (because of campactification).

 

[suprised]

For the n-th time: extra dimensions should not be taken too literally. Rather they represent one way to parametrize "internal" degrees of freedom; or "matter fields". Generically they even don't have in interpretation in terms of higher dimensions; only in limiting cases this is so.

So what the necessity of those "extra dimensions" translates to, is that string theory _requires_ extra matter fields besides pure gravity. This is a feature rather than a drawback! AFAIK no other approach to gravity seems to be able to come up with such a constraint, which then means no predictions at all for particle physics.

Whoever is obsessed by not liking "extra dimensions", is invited to think about them simply as a natural device to generate quarks, leptons, higgs fields.

 

[Paulibus]

This sort of discussion is to be found in "Higher Speculations -- Grand Theories and Failed revolutions in Physics and Cosmology" by Helge Kragh, O.U.P, 2011, where string theory is described in the context of previous attempts to understand the fundamental underpinnings of nature.

The French might use a shorter description: "la haute poppicocquerie" for such non-Baconian speculations.

 

[suprised]

One should better have scientific discussions, rather then books of opiniated non-scientists, who hardly can judge the subject.

 

[DanF]

There is no reason to question Helges qualifications. If he can't discuss unification, nobody can. After 40 years of calculation, string theory hasnt produced anything usefull and hasnt anything to say about any experiment. It may someday qualify as science, but so far it is only speculation.

About Helge:
After graduation from the University of Copenhagen in Physics and Chemistry, and a period as teacher in gymnasium schools, Helge Kragh became Associate Professor at Cornell University, Departments of History and Physics. Later, he took positions as Curator at the Steno Museum for Science and Medicine and Professor of the History of Science at the University of Oslo, Norway. Since 1997, he has been Professor of the History of Science and Technology, University of Aarhus, Denmark. He is a Member of the Royal Danish Academy of Science, the International Academy for the History of Science, and of the European Academy of Science. He was President of the European Society for the History of Science

 

[Physics Monkey]

Welcome, DanF.

Helge seems qualified to me but as a historian and (perhaps) not as a practicing physicist with a knowledge of string theory. In this sense, his academic credentials are not relevant for surprised's objection.

Why do you say "If he can't discuss unification, nobody can"?

Also, I must disagree with your claim that string theory hasn't produced anything useful. Forgetting about mathematics entirely, holographic duality has already been at least a little bit useful, and it may become considerably more useful in the future. String theory has also stimulated certain theoretical developments that have a direct impact on current experimental systems e.g. 2d conformal field theory.

 

[Paulibus]

Thanks, Danf, for the support of Helge Krach, who is a concientious scholar, rather than an "opinionated non-scientist". A reading of his book is a salutory experience for all chattering ex-African ape-scientists (as we have recently come to recognise we are). We're very prone to "poppicocquerie"; evolution has hard-wired it into all of us --- including me, of course.

But then I'm not an ex-African, which helps with perspective.

 

[John232]

Well, I guess they say that the one's who can't do, teach. And last time I checked everybook at the local library about physics was written by a physics teacher... I don't see how that makes them a non-scientist, I feel that comment in itself is an uneducated opinion. Any book on string theory isn't very descriptive on how the theory actually works and tends to be a small foot note in the back of the book, a very generalized description. I think it keeps people from really being able to talk about it and how and why it works, because honestly I think no one really knows. But I do know that none of them claim that 11 dimensions is preferred in any way to any other amount of dimensions, and the "prediction of the string framework" in itself would be what adds extra dimensions since it would take extra dimensions in order to create that framework. It isn't testable because it doesn't predict anything that would act differently than any other theory that is testable. No significant difference, if it did predict a significant difference I would hope that they would be able to run a test to distiguish it.

 

[John232]

If I could, I would develop a string theory that only uses 3 spatial dimensions and 1 time dimension and then say, "It couldn't be proven experimentally", just to screw with everyones head.

 

[juanrga]

The scientific method says that if experiments or observations falsify a theory, that theory must be rejected.
String theory requires space to have 9 dimensions. But observation shows that our space has only 3 dimensions. This alone should falsify string theory.

I know that scientists have amended an ad-hoc hypothesis that 6 of the dimensions are curled up too tiny to observe. But there is no experimental evidence of this. And the theory does not predict or explain why 3 dimensions should be large and 6 tiny.

If you add enough ad-hoc hypotheses, any theory could be accepted. The Earth-centered universe could still be believed if you add enough epicycles and other unsupported ideas to explain the motion of the planets. But science usually rejects this kind of fixing up of a theory (mainly due to Occam's Razor). So, without ad-hoc hypotheses, shouldn't string theory also be rejected?

Does any future experiment even have the potential to falsify string theory? If so, what might that experiement be? If not, then string theory is not science. It is a religion.

Yes string theory is a religion. Some string theorists as Gates admit it:

String theory is often criticized as having had no experimental input or output, so the analogy to a religion has been noted by a number of people. In a sense that's right; it is kind of a church to which I belong. We have our own popes and House of Cardinals.

You would not criticize the whole scientific community by the insanity and dishonesty of a small group of people.

 

[John232]

Gates wouldn't be the only one skeptical about string theory. I have noticed scientist who talk about it on TV seem more sure about it than in their own book...

On that page I couldn't help but notice, "The carrier of the gravitational force is the graviton; the carrier of the electromagnetic force is the photon; the carrier of the strong force are things called gluons. " Only one of these force carriers in quantum mechanics has been verified to actually exist. So then couldn't you say that quantum mechanics is also a religion? Then again, most religions do put the photon (or light itself) as the figure of their God.

I think string theory has just gotten stuck in a rut in the scientific process, it has just taken it a long time to get to the experimental phase, this is understandable since they keep changing the theory. I don't think the scientific process has a time limit it has to keep in order to stay sceince. We will just have to force ourselves to be patient enough for it to finish the process, and I predict we will be waiting for it to do this for a very long time. It could take the next greatest sceintist of all time to be able to prove or disprove the theory, not mention his ability to prove that to everyone else as well.

Personnaly, I would not pursue string theory, because I think it is a little far fetched myself and would only lead to a dead end in a scientific career. I thought I would rather check out the worldlines of particles as though they themselves where strings. I wouldn't want to get caught up into a bunch of mathmatical hoopla.

 

[dhillonv10]

One should better have scientific discussions, rather then books of opiniated non-scientists, who hardly can judge the subject.

I was about to post this but surprised took care of it. To OP: please read up more on the subject, there is a lot to string theory.

 

[kochanskij]

Thank you to all who posted an opinion about string theory. I am not saying that it is "wrong". I'm just saying that it is far from being proven correct.

In religion, one assumes that the Bible is true. If an observation is in conflict with it, we must figure out why the observation is wrong or our interpretation of it is wrong.
In String Theory, some scientists seem to assume the theory is true. If an observation is in conflict with it (like space having only 3 dimensions), they figure out why the observation is wrong (compactified dimensions or membranes).
If String Theory does not predict which of the 10^500 topologies extra dimensions should take, they assume there is an unseen universe for each one of them (landscape).
I think String Theory is sometimes being treated too much like the Bible, in that some people assume every word of it is true, no matter what observation shows.

We scientists understand the scientific process and the status of strings, but the general public does not. Popular writers like Brian Greene and Kaku should not say that string theory and its predictions are facts. They usually put string theory at the same level of confidence as relativity or quantum mechanics. These theories have been confirmed by thousands of experiments but string theory has been confirmed by none.

 

[juanrga]

Thank you to all who posted an opinion about string theory. I am not saying that it is "wrong". I'm just saying that it is far from being proven correct.

In religion, one assumes that the Bible is true. If an observation is in conflict with it, we must figure out why the observation is wrong or our interpretation of it is wrong.
In String Theory, some scientists seem to assume the theory is true. If an observation is in conflict with it (like space having only 3 dimensions), they figure out why the observation is wrong (compactified dimensions or membranes).
If String Theory does not predict which of the 10^500 topologies extra dimensions should take, they assume there is an unseen universe for each one of them (landscape).
I think String Theory is sometimes being treated too much like the Bible, in that some people assume every word of it is true, no matter what observation shows.

We scientists understand the scientific process and the status of strings, but the general public does not. Popular writers like Brian Greene and Kaku should not say that string theory and its predictions are facts. They usually put string theory at the same level of confidence as relativity or quantum mechanics. These theories have been confirmed by thousands of experiments but string theory has been confirmed by none.

Popular books denouncing the dishonesty of some string theorists have been published and gained attention in the media up to a point that today many laymen are sceptics about the real status of string theory (nonsense)

The Trouble With Physics: The Rise of String Theory, The Fall of a Science, and What Comes Next

Not Even Wrong: The Failure of String Theory and the Search for Unity in Physical Law

 

[suchal]

the string theory(means equation) clearly says that there must be 11 dimensions for string to move to make the system run. The equation is derived from approved physics equations and those are accepted by all physicists, then why some does not believe in string theory. if it is about that it can not be explained through experiments than the answer is that now the physics has reached such an extent that our power, energy, logic, vision and resources are too small to small, whereas we are too big to do experiment with strings.

 

[griswold]

What do you think of this:
http://arxiv.org/abs/0806.0051

There is interview with Dr James Gates, a string theory scientists, he says (or he and other scientists from his area) that computer code (one used in error correcting in computer science) - "Doubly-even self-dual linear binary error-correcting block code," first invented by Claude Shannon in the 1940's, has been discovered embedded WITHIN the equations of superstring theory

So this is like food for thought for all those who support idea that our universe is simulation :)

 

[RoshanBBQ]

the string theory(means equation) clearly says that there must be 11 dimensions for string to move to make the system run. The equation is derived from approved physics equations and those are accepted by all physicists, then why some does not believe in string theory. if it is about that it can not be explained through experiments than the answer is that now the physics has reached such an extent that our power, energy, logic, vision and resources are too small to small, whereas we are too big to do experiment with strings.

I was watching http://www.amnh.org/news/tag/isaac-asimov-memorial-debate/ and Brian Greene said something along the lines of "I do not believe in string theory. I think it might be our best bet so far, and I'm enthusiastic about it."

You have to remember that belief in science comes from observation. A lack of observation does not mean it's not science, however. It just means you should not believe it. Science, in part (a large part), is the search for observations -- it isn't only a statement about what should currently be believed. So of course string theory is science.