> On 6 Aug 2019, at 20:00, 'Brent Meeker' via Everything List > <[email protected]> wrote: > > > > On 8/6/2019 6:38 AM, Bruno Marchal wrote: >>> If the QC does its task effectively, the output basis qbits will be put >>> into definite states, >> >> Relatively to the observer, but in the global state, the observer will >> inherit the superposition state, by linearity of the tensor products and of >> the evolution. > > In something like Shor's algorithm there is only one final state with > non-vanishing probability. Yet this is the kind of algorithm that Deutsch > cites as proving there must be many worlds.
Can you wrote a classical emulator of the algorithm of Shor which does not emulate the “parallel computation”? I have never succeeded. I agree that this proves nothing, but QM without the superposition (the parallel histories) does not (yet) make any sense to me. That there is only one final state does not explain how shor’s algorithm works without the intermediate superposed states. It is the same with Deutsch Josza problem, and some others. In fact, as Deutsch said and explain well, even the two slits experiment is hard to explain without attributing a physical existence to the superposed state. The difference of the behaviour between pure sate and mixture seems to impose some notion of parallel histories. Bruno > > Brent > > -- > 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] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/10717b73-00cf-2353-0415-42497db85c3e%40verizon.net > > <https://groups.google.com/d/msgid/everything-list/10717b73-00cf-2353-0415-42497db85c3e%40verizon.net?utm_medium=email&utm_source=footer>. -- 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/6103D4C6-F077-4486-BF45-3D1C0336D1A8%40ulb.ac.be.
