On 22 November 2014 05:36, John Clark <[email protected]> wrote: > On Fri, Nov 21, 2014 Bruno Marchal <[email protected]> wrote: > > >> Yes the Schrodinger Wave Equation is easily reversible (and it's >>> continuous and deterministic too), but with regard to the reversibility of >>> time that's a irrelevant fact because the SWE is a unobservable >>> abstraction. >>> >> >> > To be sure I was reasoning assuming the usual non relativistic SWE. >> Then it is reversible in the same unitary sense that quantum computer gates >> are reversible, which includes the usual notion of time. >> > > That is incorrect because computer gates are observable but the SWE, both > relativistic and non relativistic, are unobservable, only the square of the > wave is observable and then only as a probability. So the SWE may be > reversible but it's square is not; if 4 is the product of two integers > there is no way to know if they were 2 or -2, so you can't reverse things > and find the previous probability, much less get back into the actual > previous state with 100% certainty. > > This certainly sounds like a valid point - Bruno? The SWE (or matrices etc) are assumed to be real, but are unobservable. Their effects are observable but not time reversible...yes?
I'm not sure where the Wheeler-deWitt equation comes into this? -- 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 http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
