On Fri, Jan 10, 2014 at 4:47 PM, LizR <lizj...@gmail.com> wrote: > "Retro-causality" (time symmetry is a better term) only exists at the > quantum level. >
Why? Where is the dividing line? And with a Schrodinger's Cat type device a quantum event can easily be magnified to a macro-event as large as desired, you could connect it up to an H-bomb. > The laws of physics are time-symmetric, but constrained by boundary > conditions. > And that is exactly what I've been saying over and over, and that is why the second law is almost always true and that is why time has a direction. > There is a very influential boundary condition in what we call the past, > namely the Big Bang, plus less influential ones in the future, > Exactly. >> And by the way, if time is symmetrical then there is no point in ever >> actually performing an experiment because you would remember the future as >> clearly as you remember the past, so you would already remember the outcome >> of the experiment just as clearly as you remember setting up the >> experimental apparatus. >> > > >I assume you're not so stupid as to think that's what I've been claiming, > so I can only assume this is a deliberate attempt at mockery, > Yes sometimes I mock people but I promise you that was not my aim this time. It's just a fact, if time were symmetrical then you'd be just as good at predicting the future as you are at remembering the past, so you'd know the outcome of an experiment before you performed it just as well as you remember setting up the apparatus. But this is not the way things are because the second law exists. And the second law exists because of low entropy initial conditions. And I don't know why there were low entropy initial conditions. John K Clark -- 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.
