On 5 February 2014 10:58, Jesse Mazer <laserma...@gmail.com> wrote: > > > On Tue, Feb 4, 2014 at 4:39 PM, meekerdb <meeke...@verizon.net> wrote: > >> On 2/4/2014 1:11 PM, Jesse Mazer wrote: >> >> >> >> On Tue, Feb 4, 2014 at 3:59 PM, LizR <lizj...@gmail.com> wrote: >> >>> There is nothing exotic about the state of a photon being determined >>> by future boundary conditions. >>> >> >> You *could* determine the state of any system in quantum theory by >> future boundary conditions, but what would be exotic is the assumption that >> neither past nor future boundary conditions are sufficient on their own, >> that you need a combination of both. That just isn't how it works in >> quantum theory, >> >> >> Some people think it is. When the past boundary condition doesn't >> predict a definite future condition, then adding a future boundary >> condition can resolve it. That's how Stenger effectively gets a non-local >> effect in an EPR experiment. >> > > If we ignore the idea of a "collapse" of the quantum state on measurement, > isn't the evolution of the wave function deterministic, so that knowing the > complete past quantum state of an isolated system is always enough to > calculate the later quantum state? Is Stenger basically arguing that the > "collapse" on measurement is not really random but is determined by a > combination of past and future boundary conditions? > > I imagine he's saying the measurement constitutes a boundary condition.
We assume no collapse, I think. Collapse IS time asymmetric, so the time symmetry argument goes out the window if wavefunctions can be shown to collapse. The MWI, however, should be time symmetric at the same level that physics is (recombining universes as often as they split). But there is a huge entropy gradient at the coarse grained level so a huge asymmetry of split-vs-merge at that level. -- 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.
