On 7 January 2014 08:36, meekerdb <meeke...@verizon.net> wrote: > On 1/6/2014 8:16 AM, John Clark wrote: > > On Sun, Jan 5, 2014 at 4:11 PM, LizR <lizj...@gmail.com> wrote: > > On 6 January 2014 06:47, John Clark <johnkcl...@gmail.com> wrote: >> >>> >>> >>> Bell's theorem holds only under a certain set of assumptions, >>>> >>> >>> >>True. As I've said many times Bell made exactly 3 assumptions: >>> 1) High School algebra and trigonometry works. >>> 2) Things are local. >>> 3) Things are realistic. >>> >> >> > In fact Bell made a fourth assumption, although he didn't realise he >> was making it until later. Namely, he assumed that time is asymmetric. >> > > I won't bother to argue if Bell made this assumption or not because it > doesn't matter, time is asymmetric. > > > 4) Time is asymmetric not just at the level of everyday experience, >> but also at the quantum level >> Bell's 4th assumption seems to me quite a reasonable one to drop, >> given that most physics contradicts it. >> > > That is incorrect, most physics does NOT contradict time's asymmetry, > thermodynamics and cosmology certainly don't. Yes Quantum Mechanics seems > to be time symmetrical but even if Quantum Mechanics tells the whole story > (and we know for a fact that it doesn't because it doesn't include gravity) > time could still be asymmetric because how a system evolves over time > depends not only on the rules of the game (Quantum Mechanics) but also on > the initial conditions. > > > But if QM without collapse is fundamental, then the dynamics are time > (really CPT) symmetric and all the observed asymmetry is a statistical > effect due to starting in low entropy initial conditions. Bell derived his > inequality assuming QM with collapse, i.e. he assumed this time asymmetry > was fundamental, not a mere statistical effect related to the low entropy > of the initial conditions of the experiment. >
Well if Bell assumed collapse (which is I agree a fundamental time asymmetry) then he built in time asymmetry, just as I said. It is, indeed, his 4th assumption. I know of only one CPT violation, and if we assume no-collapse then everything else in the universe appears to be either a (rather unlikely) knock-on effect of kaon decay or a statistical result of the entropy gradient, which is in turn derived (most likely) from universal boundary conditions like the cosmological expansion. PS It *would *have been nice if you'd started what you said "And" rather than "But" just to show that you were agreeing with me :( -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
