Strings Theory

[1veedo]

I've got a question:

 

Why is this thread in the A&C forum?

[Tesseract]

I've got a question:

 

Why is this thread in the A&C forum?

Because thats where it was created.

[Tesseract]

I've got a question:

 

Why is this thread in the A&C forum?

Because thats where it was created.

[Severian]

so, are you pro-string theory or pro-standard model?

 

They are not mutually exclusive.

[Severian]

so, are you pro-string theory or pro-standard model?

 

They are not mutually exclusive.

[ydoaPs]

Well its not really a theory at all' date=' because:

 

1)it should be consistent with pre-existing theory to the extent that the pre-existing theory was experimentally verified, though it will often show pre-existing theory to be wrong in an exact sense,

 

2)has survived many critical real world tests that could have proven it false

 

3)makes predictions that might someday be used to disprove the theory

 

4)is the best known explanation of the infinite variety of alternative explanations for the same data (Occam's Razor)[/quote']

 

 

1)special relativity and quantum mechanics did the same thing. does that keep them from being theories?

 

2)it SURVIVED the tests. that sounds to me like it is more likely to be true rather than less likely.

 

3)what predictions does it make that could disprove it?

 

4)looks like occam's razor supports string theory, but i wouldn't just go by that. if we just went by occam's razor, everyone would be a creationist(which is simpler: god created everything, or a zero dimensional object{for no appearent reason} exploded into everything we see here {and big bang doesn't actually say anything about creation, but that isn't the point}?).

[ydoaPs]

Well its not really a theory at all' date=' because:

 

1)it should be consistent with pre-existing theory to the extent that the pre-existing theory was experimentally verified, though it will often show pre-existing theory to be wrong in an exact sense,

 

2)has survived many critical real world tests that could have proven it false

 

3)makes predictions that might someday be used to disprove the theory

 

4)is the best known explanation of the infinite variety of alternative explanations for the same data (Occam's Razor)[/quote']

 

 

1)special relativity and quantum mechanics did the same thing. does that keep them from being theories?

 

2)it SURVIVED the tests. that sounds to me like it is more likely to be true rather than less likely.

 

3)what predictions does it make that could disprove it?

 

4)looks like occam's razor supports string theory, but i wouldn't just go by that. if we just went by occam's razor, everyone would be a creationist(which is simpler: god created everything, or a zero dimensional object{for no appearent reason} exploded into everything we see here {and big bang doesn't actually say anything about creation, but that isn't the point}?).

[1veedo]

Because thats where it was created.

I was being sarcastic. This thread needs moved to Modern/Theoretical Physics.

[1veedo]

Because thats where it was created.

I was being sarcastic. This thread needs moved to Modern/Theoretical Physics.

[Tesseract]

It dosnt make any predictions that could one day disprove it, thats a characteristic of a theory. Thus its not a theory just a "a bundle of competing hypotheses for a protoscience".

 

here are theory characteristics:

 

1. existing theory was experimentally verified, though it will often show pre-existing theory to be wrong in an exact sense,

 

2. is supported by many strands of evidence rather than a single foundation, ensuring that it probably is a good approximation if not totally correct,

 

3. has survived many critical real world tests that could have proven it false,

 

4. makes predictions that might someday be used to disprove the theory, and

 

5. is the best known explanation, in the sense of Occam's Razor, of the infinite variety of alternative explanations for the same data.

[Tesseract]

It dosnt make any predictions that could one day disprove it, thats a characteristic of a theory. Thus its not a theory just a "a bundle of competing hypotheses for a protoscience".

 

here are theory characteristics:

 

1. existing theory was experimentally verified, though it will often show pre-existing theory to be wrong in an exact sense,

 

2. is supported by many strands of evidence rather than a single foundation, ensuring that it probably is a good approximation if not totally correct,

 

3. has survived many critical real world tests that could have proven it false,

 

4. makes predictions that might someday be used to disprove the theory, and

 

5. is the best known explanation, in the sense of Occam's Razor, of the infinite variety of alternative explanations for the same data.

[jeheron]

Could you please simply explain the basic gist of the String Theory?

[Severian]

Instead of particles being points, they art extended objects like strings (hence the name). It was originally hoped that the different vibrational modes of the strings would correspond to different particles, so that, for example, the muon and an electron might be described by the same string vibrating at different frequencies. This didn't quite work, since the excited modes tend to give very very big masses to the particles.

 

There were also problems with describing fermions as strings, until it was realised that one could incorporate them by including "supersymmetry". The result was supersting theory.

 

One of the most interesting aspects is the difference between open and closed strings. Open strings are when the string just stops (like a small piece of string). Closed strings are when the string forms a closed loop. Whether they are open or closed leads to different properties. Also some string theories treat left handed polarisations differently from right handed ones, and are called "heterotic". Hence the fashionable modern string theory is "heterotic string theory".

[1veedo]

For the most part it doesnt matter if a string is open or closed. Though when dealing with cosmology, gravity, or complex energy exchanges this factor does need to be recognized.

 

Also, strings technically arent strings. The original models had 1D objects but it now seems that string theory contains all kinds of unique dimensional membranes (branes for short) all the way to even 8D branes in some theories.

 

The good thing abotu string theory is its ability to tackle ideas such as pre-big bang and black holes because it loses infinities in a singularity (plank) and makes unified field theory work.

 

One thing to remember is that there is absolutely no data for string theory. I consider it a hypothesis because, although it holds a lot of theoretical evidence, quantum field theory holds some data as well and so far no empirical test has been done to favor either one. However, in the long run I’m optimistic that string theory will take the prize.

 

http://superstringtheory.com/

 

That's a good site for beginners. I recommend looking at their book's section.

[Severian]

Sorry, I made a brain fart there. I didn't really mean open and closed strings when refering to heterotic. I meant whether the theory treats left and right handed states the same.