On Sat, Aug 3, 2019 at 9:59 AM Jason Resch <[email protected]> wrote:
> On Fri, Aug 2, 2019 at 6:44 PM Bruce Kellett <[email protected]> > wrote: > >> On Sat, Aug 3, 2019 at 9:36 AM Jason Resch <[email protected]> wrote: >> >>> On Fri, Aug 2, 2019 at 5:18 PM 'Brent Meeker' via Everything List < >>> [email protected]> wrote: >>> >>>> On 8/2/2019 1:41 PM, Jason Resch wrote: >>>> >>>> [Brent]One. It's a unitary evolution of the input state. >>>>> >>>> >>>> We were speaking of computational states. Are you saying there is only >>>> one computation state involved in Shor's algorithm? What causes the >>>> interference necessary to yield the correct answer, if not these numerous >>>> computational states? >>>> >>>> The interference is in the measurement which Deutsch would say projects >>>> out onto one of the multiple worlds...the non-unitary step. >>>> >>> >>> Does anyone claim interference happens during the measurement? In >>> the double slit experiment the interference happens when the two photons >>> overlap in their position, not when they strike the photographic plate. >>> Deutsch says as much in his introduction to Fabric of Reality when speaking >>> of shadow selves and shadow photons. >>> >>> In any case, you have still managed to avoid the question of the reality >>> of the 10^1000 intermediate computational states. I won't press for an >>> answer if you don't have one. >>> >> >> Brent is correct. There is only ever one state -- one vector in Hilbert >> space. The computation involves nothing more than unitary rotations of this >> vector in Hilbert space. The final result is obtained by projecting this >> state on to some set of basis vectors. None of the intermediate projections >> on to arbitrary basis vectors is "real" in any sense, since such basis >> vectors are arbitrary. >> > > A lot of computational work gets done for by something that isn't real in > any sense. > The number of dimensions of the Hilbert space is real enough, even though it is an abstract space. > So, in that sense, the final measurement does do the interference because >> it involves a choice of a particular basis. Just as the spots on the screen >> behind a double-slit experiment decide the interference -- they amount to a >> choice of basis in position space -- position along the axis of the screen. >> > > So the Morpho butterfly isn't sending out blue light until you look at it? > Non sequitur. Bruce -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAFxXSLTrJ%3DRcxUdzBa3s%2BxSjQVBo56e0Gpi-JbENPbhEk1ASVA%40mail.gmail.com.
