Tuesday, November 27, 2007

Theory of Everything?

First I saw this. Then, I went to the physics archive, the democratic forum where anyone can post and found this. I printed it, skimmed it and formed a minimal impression (to the effect that it is a good idea but ways to go before it can be a theory of everything). But, I am not well versed in the relevant jargon, so I need to spend some time and talk to people who are well versed (and that is the advantage of being in a physics department, all kind of help is just a stroll down the corridor away!) before I can tell you about it. But, in the mean time do go and check out this post, and scroll through the comment thread, we have Garret Lisi in there trying to explain this stuff himself.

PS: The pretty picture is the polytope with E8 symmetry, the group that has that nice property that the fuss is all about. I know, I know, I just put it in because it is pretty :)


merlin said...

Suppose there could be a theory of everything including life on Earth. Would this not need to be a theory of everything that can't be explained as effects caused by the forces? Because, for one thing, doesn't matter as atoms and molecules exist despite the forces acting within and upon it? And for another, aren't quantum wave, spin and entanglement effects that can't be explained as effects caused by the forces?

Don't suppose you can find a physicist to help you on this. But it would be nice to think you could.

CuriousCat said...

Dear Merlin, I do not know your background, so I do not know if this answer is appropriate. Physics is a mathematical model of reality. The mathematical model could used such objects as "force" and "particles" and so on. But, fundamental physics as it stands today does not. Everything except the theory of gravity is now described by quantum field theory that does not have in it particles or forces...it just has fields. Entanglement and so on have nothing to do with forces as you say, but there are no forces anymore for me to worry about.

Also, life is but an autocatalytic chemical reaction. If you believe that physics explains chemistry (and this might be an easier thing to see for you), then definitely physics explains life as well.

merlin said...

But then there are certain crucial universal features of matter that no recognised quantum theory explains and can be thought relevant to life.

One feature is that, given just the experimental findings that matter as atoms and molecules consists almost all of the space between electrons and nuclei, how can matter exist or persist as such?

(And then it can be added that a very powerful force or interaction that acts between these components so as to attract between electrons and nuclei and repell between electrons.)

And it can be insisted that for this question to be answered there would at least need to be a sufficient explanation of the wave function in terms of how it is that this can be described.

So it could be asked: could this wave be a universal cause acting constantly in addition to the forces that prevents electrons from falling into nuclei and if so, how so or if not why not?

And to answer these questions it can be expected that there should be causal explanation of the quantum wave, which simply can't be given at least from any quantum evidence alone because, for one thing, no evidence of this wave can be directly detected by any means.

Whereas all you get in quantum theory is various conflicting interpretations that can't be confirmed or disconfirmed.

CuriousCat said...

@ merlin :"atoms and molecules consists almost all of the space between electrons and nuclei," This is the only statement I understood of the many things you are saying. And for this statement I refer you to Richard Dawkin's TED talk (posted on this blog earlier), for a little perspective, not physics as such. And as for other things, I am sorry but I have no clue what you are talking about.

merlin said...

Well actually, curiouscat, there is a little known because not widely taught (because unjustly disparaged)interpretation of quantum physics that does describe the quantum wave as an additional cause, and which Louis de Broglie called the pilot wave and David Bohm called the quantum potential that could be conceived as wrapping itself around atoms and molecules and causing the electon's behaviour as a particle. Bohm's theory being a mathematically systematic accopun that has yet to be disproved from a wide range of experimental results.

see http://en.wikipedia.org/wiki/Pilot_wave and http://en.wikipedia.org/wiki/Bohm_interpretation

And it could be asked why shouldn't this pilot wave/potential in enough need to be described to explain how matter is solid and can resist the forces acting within and upon it?

But one reason why most theoretical physicists don't like this idea is that the existence of such a cause messes up any quantum gravity type theory of everything like string theory, loop quantum gravity or Lisi's effort above.

CuriousCat said...

well merlin...I sort of see what you were saying now...but need way more effort on my part ot really see what I think about this stuff...thanks for telling me though.