On Thursday, November 30, 2017 at 4:08:20 AM UTC-7, Bruce wrote: > > On 30/11/2017 9:53 pm, [email protected] <javascript:> wrote: > > On Wednesday, November 29, 2017 at 10:40:36 PM UTC, Bruce wrote: > > On 30/11/2017 5:31 am, John Clark wrote: > > On Tue, Nov 28, 2017 at 10:59 PM, Bruce Kellett <[email protected]> > wrote: > > > > > I see no reason all the Everett worlds have the same physics, > > > > > Everettian worlds follow from assuming that the Schrödinger equation > applies everywhere without exception, so that all physical evolution is > unitary. A change in the underlying physics -- such as a change in the > value of fundamental constants, Planck's constant or Newton's constant for > example -- would not be unitary, so cannot occur in MWI. > > > > Why can't it be unitary?? Show me why if > > Newton's constant had any value other than > > 6.754* 10^-11 m3 kg^−1 s^−2 > > the sum of all quantum probabilities would no longer add up to exactly 1. > If you can really do that then you've just derived Newton's constant > directly from first principles and you should but a ticket to Stockholm > right now because you're absolutely certain to win the next nobel Prize. > > Although unitarity does mean that probabilities always sum to unity, that >> is a consequence of unitary evolution, not a definition of it. A unitary >> transformation is one that can be reversed: so the unitary operator U can >> be written as exp(-iH), for example, and the complex conjugate (or the >> adjoint for hermitian operators) is the inverse transformation. >> > *Considering the evolution of the wf, if there exists a DE that describes >> the collapse process, would it necessarily be nonlinear? Is nonlinear a >> problem; that is, what is the downside to nonlinear? How would it effect >> the issue of hidden variables? TIA, AG * >> > Collapse would be non-linear and non-unitary -- intrinsically non-reversible. This is not necessarily a problem since there are plenty of non-linearities in physics. It has nothing to do with hidden variables.
*Why would it be non linear? Brent claimed (on page 1) that if the QM could be made deterministic, say by a DE that described collapse, it would imply awful consequences, such as the future determining the past. Would making QM into a deterministic theory imply an inconsistency in the postulates of QM? TIA, AG* > ... -- 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
