SoylentNews is people
SoylentNews
It's one of the most brilliant, controversial and unproven ideas in all of physics: string theory. At the heart of string theory is the thread of an idea that's run through physics for centuries, that at some fundamental level, all the different forces, particles, interactions and manifestations of reality are tied together as part of the same framework. Instead of four independent fundamental forces -- strong, electromagnetic, weak and gravitational -- there's one unified theory that encompasses all of them. In many regards, string theory is the best contender for a quantum theory of gravitation, which just happens to unify at the highest-energy scales. Although there's no experimental evidence for it, there are compelling theoretical reasons to think it might be true. A year ago, the top living string theorist, Ed Witten, wrote a piece on what every physicist should know about string theory. Here's what that means, translated for non-physicists.
(Score: 1) by Ramze on Tuesday December 06 2016, @03:52PM
Well... String theory, M theory, and p-brane theory (yeah, they actually named it that. lol) are all frameworks for possible realities. No one has yet discovered which derivation of the theory actually fits our universe best, so it can't make proper predictions about unknowns.
Quantum mechanics makes predictions, and string theory basically uses particle physics discoveries and quantum mechanics predictions to narrow down which formulas describe our universe in string theory. String theory itself isn't actually useful for anything yet other than parroting quantum mechanics. It may never be. Or, maybe we'll get lucky and figure out which parameters for string theory correspond with our universe (if any) and literally discover everything.
String theory is short for superstring theory... which itself is short for super-symmetric string theory. We don't even know if super-symmetry exists, and if it doesn't, at least our explanation of it collapses. It's possible the whole thing is hogwash as it was constructed to make the quantum mechanical math more elegant, but hasn't really shown much otherwise.
Well... I take that back -- the Higgs Boson was predicted long before string theory, but the Higgs field is what allowed string theory to look so elegant to begin with -- by separating out the mass terms to make a lot of the equations more unified. In a sense, the Higgs verified string theory was on the right track. It could still be wrong, though.
(Score: 0) by Anonymous Coward on Sunday December 18 2016, @04:54AM
Armchair physicist here.
I've always been confused by popular accounts of "string theory". Specifically, I believe the original string theory, and even other variants are not necessarily supersymmetric, and yet I see popular accounts saying string theory means superstring theory means supersymmetric string theory. The first part of that seems invalid if string theory is not synonymous with supersymmetric string theory.
Not quite sure what I'm missing here. What would a non-SUSY string theory be called in the literature, and are there reasons it's not really viable?
Thanks