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→Non-Locality and Quantum Field Theory
:I beg you to open your mind and learn here, for your own sake. Look at how you refused to address my simple point. Instead you cling to your perception of what you think others believe.--[[User:Aschlafly|Andy Schlafly]] 09:11, 19 May 2009 (EDT)
:I beg you to open your mind and learn here, for your own sake. Look at how you refused to address my simple point. Instead you cling to your perception of what you think others believe.--[[User:Aschlafly|Andy Schlafly]] 09:11, 19 May 2009 (EDT)
How can I address your point, when there's no way to know what IS your point?
Is your point "All evidence is against your view"? OK, dish it out. Just list the top 3 evidences showing that action at a distance is the only way possible for particles to interact.
My point is: the horrible paragraph in the Intro about non-locality and field theory, incorrectly implies field theory is defective. It is not. Field theory is the most successful theory in the history of science. Weinberg's statement about field theory not being "robust" cannot be assessed by the reader because "robust" is not defined in this context. Weinberg's speech was written in '79, his criticisms were resolved by later successes of QCD and QED, as Wilczek described. That paragraph should go. You're trashing relativity and field theory too. Why?
Write 3 sentences. Top 3 evidences that action at a distance is the only way for particles to interact.
--[[User:Cuddlytakun|Cuddlytakun]] 16:10, 21 May 2009 (EDT)
:How about ONE evidence, Cuddles? Like the evidence that you refused to go beyond talk and ''improve the articles''. Nothing happened at all by way of action of your part, either in this article, nor in [[Quantum field theory]], which definately needs improvement. Instead of action, all we get is gab from you. [[User:Karajou|Karajou]] 16:23, 21 May 2009 (EDT)
OK. I have significantly updated the page on [[Quantum field theory]]. EdPoor said the page needed writing, and Karajou asked me to make an improvement, so I rewrote it. Now I'm going to fix the last paragraph in the Intro, which trashes field theory. Here I'm going to explain and justify my rewrites, line by line.
"...which [Relativity] assume that time is an intrinsic part of space and assumes absolute locality." I have rewritten as "Unlike Newtonian mechanics, in which space and time intervals are each invariant as seen by all observers, in SR the only invariant quantity is a quadratic combination of space and time intervals (x<sup>2</sup> - c t<sup>2</sup>)."
It does not make sense to say that in relativity "time is part of space", nor is space part of time. The theory is about a space-time continuum, not time as part of space! They're symmetric in the metric, but with different signs.
"The non-locality of quantum mechanics and Newtonian physics contradicts the theories of relativity" I have rewritten as "The (assumed) instantaneous transmission of Newtonian gravitational effects contradicts special relativity." This statement is more accurate.
What does it mean to say "Quantum mechanics is non-local"? Vague. Quantum wavefunctions are non-local, and in the event of quantum entanglement (correlation) the wavefunction is multi-particle. But this is not relevant to relativity because real particles (unlike virtual particles) cannot transmit info faster than light (light cone restriction conserves causality). No entanglement experiment (e.g. teleportation) can transmit info faster than light, in fact teleportation requires classical info transmission SLOWER than light, look it up.
The Copenhagen interpretation of the collapse of the wavefunction upon observation is non-local but it is an interpretation, and likewise, cannot transmit info faster than light.
'Causality breaks down under relativity if information can be transmitted faster than the speed of light. In addition, the uncertainty principle suggests that light photons must sometimes travel faster than the speed of light despite the assumption of relativity; "[t]he only known way to resolve this tension involves introducing the idea of antiparticles."[6]'
I have rewritten as: 'In quantum mechanics, the uncertainty principle suggests that virtual particles can sometimes travel faster than the speed of light which would violate causality, but "[t]he only known way to resolve this tension involves introducing the idea of antiparticles."[6] Consequently, in 1928 Paul Dirac derived the Dirac equation, one of the first quantum mechanical equations compatible with special relativity, by which Dirac predicted the existence of antimatter. Four years later, antimatter (the positron) was discovered by Carl Anderson, as successfully predicted beforehand by relativistic quantum mechanics.'
This statement accurately reflects the facts that, first, some quantum mechanical equations are compatible with SR (e.g. Dirac equation, Klein-Gordon equation), and that Dirac's prediction of antimatter before its discovery was a SUCCESS for relativistic quantum mechanics, not a failure! Which is the point Wilczek was making in the citation from his Nobel speech: success, not failure.
"Quantum field theory is another attempt to partially reconcile relativity with quantum mechanics. But "quantum field theory, which was born just fifty years ago from the marriage of quantum mechanics with relativity, is a beautiful but not very robust child."[7]" I have rewritten as "[[Quantum field theory]], a generalization of quantum mechanics, is fully compatible with special relativity but not with general relativity."
I have deleted the quote from Weinberg because it gives the inaccurate picture that there's something wrong with field theory. There isn't. The [[Quantum field theory]] article lists some of its many successes.
[[User:Cuddlytakun|Cuddlytakun]] 16:46, 22 June 2009 (EDT)
== Proof ==
== Proof ==