In the past, many theoretical physical theories based mainly on mathematical models and some observations we're able to appropriately explain phenomena that took decades to confirm or disprove.
My question is this - is M Theory a mathematically coherent theory that unifies relativity and quantum in a way that explains the multiverse? The way Stephen Hawking talks about makes it seem to be, but I'm having a hard time looking into it.
Of course, just because it's mathematically possible doesn't mean it's physically accurate. But it'd still be incredibly significant if we did in fact discover at least a possibility.
>>7749472
It's untestable and doesn't make any predictions.
In other words, garbage.
Also, does imaginary time fit into M - Theory or is it a standalone model? Is it quantum based or derived from relativity?
Unless it's too off topic, could someone give a brief summary of it for someone interested in physics who isn't mathematically inclined? All the summaries I've found seem a bit over my head in that department.
>>7749475
Christ, you didn't read my post. I am not talking about whether it is physically accurate or whether we have a means of testing it. I'm asking if i's mathematically coherent in addressing the issue at hand. If you don't know then just stfu
>>7749475
>I've never studied physics before. But watch me run my mouth.
>>7749472
>multiverse
Please stop.
M-theory is not a fully formulated theory. It is an 11 dimensional quantum theory whose leading low energy effective action is D=11 SUGRA.
It can thought of as a sort of unification of the 5 superstring theories.
M-theory with one dimension compactified on a circle corresponds to Type IIA superstring theory.
M-theory with two dimensions compactified on a two-torus corresponds to Type IIB superstring theory.
and so on for type1, and the heterotic theories.
Another connection between M-theory and the superstring theories is through D=11 SUGRA.
Each superstring theory has a corresponding low energy effective action that is a D=10 SUGRA theory. These D=10 SUGRA theories can all be obtained through a dimensional reduction of D=11 SUGRA.
There are attempts at a full description of M-theory, like matrix string theory, but they tend to only work in special cases if at all.
So what we do know about M-theory is mainly just from studying the various dualities that link it to the superstring theories and SUGRA. And also information gained from studying non-perturbative objects in the theory, like the M2 and M5 branes.
The math we have so far is sound, but the theory is far from complete.
>>7749505
There's countless well renowned theoretical and experimental physicists who've used the term.
Get the fuck over yourself
>>7749472
>>7749518
OP, you use the exact phrase
>in a way that explains the multiverse?
as if "the multiverse" is an experimental observation that we now must explain within our physics theories. I'm sure you know the multiverse has not actually been observed, so there is not really anything to explain.
>>7749479
If by imaginary time you mean do we use wick rotations? Yes, all the time.
>>7749538
That's a good point. But too many discoveries seem to imply a reality with countless universes that I'd imagine a TOE (like M theorists claims to have) would have to address that as well.
I respect experimental physics, and by no means want to develop a perspective that isn't based in reality (aka most philosophy). My goal here is to see just how strong this M theory is, and if our collective minds have been able to theorize a legitimate possibility of everything. More so than what we know, I want to know if we know.
>>7749966
>But too many discoveries seem to imply a reality with countless universes
This is untrue. There are multiple theories which allow for the possibility of a multiverse. But none of them necessarily imply that one exists. M-theory is no different.
> if our collective minds have been able to theorize a legitimate possibility of everything
As I said here, >>7749507 , M-theory is no where near a complete theory.
>>7750005
To me it really does seem so though. If (for the sake of argument, I'm not sure how what evidence we have for this) our universe developed from an inflated quantum fluctuation in expanding, energy filled space, this would absolutely imply that there are countless universes, no?. I absolutely concede that I know way too little of these things to say anything with any certainty, which is exactly why I'm here asking.
>>7750005
and thanks a lot for taking the time to write that relatively in depth summary earlier, I'm trying my best to understand it.
