|
It seems to me that Bell's Theorem suggests that the current suppositions in particle physics of particles interacting by virtual particles (thus removing the action at a distance) cannot be a totally correct picture? After all, if that is all there is, and we can simply all the interactions to that, we will have a theory involving nothing else but local (hidden) variables, and that cannot be complete can it?
I was also pondering the axioms of Bell's Theorem, namely the implicit assumption that there is a reality outside of observation, so that even if you are not observing a variable, it nevertheless exists. I can't think of anything which could show this one way or another, though I am leaning towards existence. One thing that sort of half assedly illustrates it is tunneling, where you have a definite existence of a "pilot wave" in a forbidden region, which you cannot in principle ever observe, yet must be there.
>.<
|
...
Thanks... now I'll probably be spending the next two hours on wikipedia looking up this stuff...
|
Yeah, screw those electrons getting into places they shouldn't be. And protons. Bad tunnelers, bad! >_>
|
On March 05 2008 15:47 zer0das wrote: Yeah, screw those electrons getting into places they shouldn't be. And protons. Bad tunnelers, bad! >_>
They're not bad :-P And besides, you can view this happening in your backyard or kitchen or bathtub with some separators :-). Bring the separators, be them glass walls or whatever closer and closer together, and woot! Whatever wave you started on side will propogate to the other, and you won't see shit in the space in between :-D (Doesn't work quite as sexily with water waves though >.<)
|
this is not a real theorem, more like a conjecture.
|
|
Conjecture means it hasn't been proven. For example, Fermat's last theorem was only a conjecture until like 10+ years ago.
|
Russian Federation4235 Posts
It depends on how you look at it in philosophical context. From a positivist viewpoint it ain't exactly "reality out of observation", you don't really care what's inside as long as it's fundamentally unobservable. Imagine a black box that emits signals. As long as it's fundamentally impossible to look inside, "inside" itself doesn't exist (or, to be 100% precise, it's existance and nature is not a scientific question), just a black box as it is, noumen.
Same thing with virtual particles - we might call them whatever, but quantum mechanics allow their existence as a mathematical abstraction and that abstraction happens to be useful in calculations.
However, I'm afraid I can't say much more on the subject, I didn't study particle physics beyond the basic level (standard model, CPT-theorem and such).
|
Seemed decently valid to me. While you can still recover Bell's Inequalities, from which Bell's Theorem sort of came out of, without recourse to locality, hidden variables, etc, it seems that the statement of the theorem nevertheless is valid. Besides, in physics you don't get that much closer to theorem status than this.
No comments about the implications of Bell's Theorem on the virtual particle theory of the primary "forces"?
|
lol BluzMan u posted same time as my previous post, never noticed it until now XD
Yea that was the thing, how the models don't necessarily reflect reality, just may be convenient ways to represent it. Such as the 3 different models which came out of QFD, all with different premises but giving more or less the same predictions. Makes me wonder how you could ever know what's really out there, if the only way to do so necessarily involves disturbing it.
|
Russian Federation4235 Posts
Afaik, the modern view on it states that you can't really what it really is since no matter what we assume, there ain't any way of verification other than experiment and experiment is limited by that Heisenberg guy (basicall,y, any observation of the system unpredictably and irreversibly changes that system). Also, afaik, this has also something to do with the "identifying problem":
R(t)=I(t)*S(t),
where S - incident signal, I - instrument function, R - result signal, * - convolution symbol. it corresponds a singal that passes through some system and gets altered there. For processes of such kind, it's possible to identify the instrument function knowing both signals. However, the problem of restoring the incident signal when you know R and I does not have a general solution, only soluble numerically or analytically for special types of the function I, but not for any type.
However, future theories (M-theory is a future theory as it's not generally accepted) are somewhat awkward since they involve points that are fundamentally impossible to prove, but they're still underdone, and, frankly, I don't know them that well. Physics is in a strange state now where a unfied theory is still not done/accepted while existing theories have evident flaws. QED has it's infinite energy vacuum, GTR has it's energy-impulse tensor that doesn't behave like one and infinite potential particles that too result in infinite energy after integration.
|
yea thats the thing :-( stuff like that left me >.<
|
wait what animal does does Feynman stand for?
|
|
|
|