What is string theory?

Question

What is string theory?

Answer 1

String math is not really a theory, yet, because it can't predict anything. It is an attempt to provide a mathematical space which will include the standard model of particle physics as a subset of string space. With a little tweeking, it could include just about any alternative theory, as well.

I just watched a 24 lesson course, "Particle Physics for Non-Physicists", on DVD (free from my public library). The lecturer said he would have to spend several years studying string math, just to explain what it is.

Answer 2

It's the thing that proves even a lot of so-called smart people can be duped just as easily as a moron. Which I guess makes them just as stupid as the moron. String theory is a bunch of highly complex mathematics masquerading as a scientific "theory" only it has none of the requirements that would make it a theory. It has not fulfilled any of the things claimed for it during the 20 or so years of its existence. Don't let the fact that a person has a PhD in something lead you into thinking that that person is actually smart. So don't let a bunch of fast talking, can't get a real job, scientist types dupe you into thinking that they can really explain how the universe works. They are just a lot of nothings tinkering at things that the majority of the world - more concerned with food, a place to live, etc - has absolutely no interest in whatsoever.,

Answer 3

The long answer uses a lot of higher mathematics that most mathematicians don't understand.

The short answer also uses a lot of higher mathematics that most people don't understand.

The brief answer is that string theory is that idea that all matter is composed of waves that are resonating back and forth.  For example, if you pluck a string on a violin, it will move so quickly it will appear to be an ellipsoid (a three dimensional shape, not a two dimensional line(this is called a standing wave)).  Now imagine that infinitely smaller and infinitely faster.  That is matter according to string theory.

This theory relies on the idea that matter and waves are essentially interchangable because energy is related to mass... E=mc^2.

Answer 4

11 dimensional string theory, (and 26 dimensional M theory), has not produced anything.

It is possible that the extra 7 dimensions of space in string theory, (that are not perceived), are mathematical deception that first appeared with 5 dimensional Kaluza-Klein Theory.

String theory is possibly deception involving adding dimensions of space to the already existing 3 dimensions of space one dimension at a time at 90 degree angles to the previous dimension.

That string theory is possibly invalid is stated at the end of the wikipedia article on string theory.

Answer 5

VERY basically, string theory was developed in the mid 80s as an attempt to provide a Theory of Everything, or more appropriately unifying gravitational force with the other 3 elementary forces.  At a very high level, string theory assumes the universe has more than 4 dimensions (3 space, 1 time) usually 10 or 11 (or more!).  These extra dimensions are curled up extremely tightly so that they are undetectable.  Particles, instead of existing only in our 4 dimensions, are actually vibrating strings that exist in 10 or 11 dimensions (depending on which variety of string theory you prefer).  

Different wave lengths and frequencies on the strings determine what sort of particle it appears to be in our 4 dimensions.  Strings, as they travel through time, can split and join with other strings creating new particles or appearing to exchange them.  For example, imagine two particles that have mass.  Quantum theory postulates that these two masses will exchange gravitons.  In string theory this exchange looks like an "H" with each mass particles being the vertical lines or strings and the middle line being the graviton string.

Anyway, string theory has a lot of problems and has fallen out of favor by most theoretical physicists in favor of M-brane theory.