On Monday, July 30, 2018 at 5:08:24 AM UTC, Jason wrote: > > > > On Sun, Jul 29, 2018 at 10:30 PM, <[email protected] <javascript:>> > wrote: > >> >> >> On Monday, July 30, 2018 at 3:11:47 AM UTC, Jason wrote: >>> >>> >>> >>> On Sun, Jul 29, 2018 at 6:44 PM, <[email protected]> wrote: >>> >>>> >>>> >>>> On Sunday, July 29, 2018 at 11:23:49 PM UTC, [email protected] wrote: >>>>> >>>>> >>>>> >>>>> On Sunday, July 29, 2018 at 10:31:05 PM UTC, Jason wrote: >>>>>> >>>>>> Quantum computers represent a disproof of the conjecture that the >>>>>> wave function is merely a convenience or tool for estimating >>>>>> probabilities >>>>>> of experimental outcomes, rather than something that is real. The >>>>>> reason: >>>>>> it does things we cannot. >>>>>> >>>>>> Jason >>>>>> >>>>> >>>>> Can you be specific? Why does quantum computing depend on both states >>>>> of a qubit(?) be occupied simultaneously? Can the system toggle between >>>>> those states, yet not be in both simultaneously? Couldn't quantum >>>>> computing >>>>> work, or say be conceptualized with his model? TIA, AG >>>>> >>>> >>>> IOW, is the model of superposition you use in quantum computing a >>>> necessary condition for its success, or could you use the information-only >>>> model of the superposition and get the same result. AG >>>> >>>>> >>>>>> >>>>>> >>> >>> In order to explain the final result of the computation appearing in the >>> measured qubits, each of the intermediate states must have existed and >>> interacted, >>> >> >> *What are the intermediate states? * >> > > Like a computer program before it prints its result and halts, the quantum > computer takes advantage of the unmeasured isolated QM system which can > enter a superposition of many simultaneous states, in the end, before the > quantum computer prints its result, it must use interference effects to get > all parts of the wave function to agree before it halts and gets measured. > If it doesn't then whoever measures the result of the quantum computer will > become entangled with that multi-valued state (causing that observer to > split). > > >> >> *Isn't a qubit system a two-state system? AG* >> > > A qubit will provide only 1 of 2 possible values when measured, but it can > take on an arbitrarily large number of states within the superposition >
*But the superposition of a qubit has only two components, and using the SWE only the probability of these two states change in time. So when speaking of one qubit, I have no idea what you mean by "an arbitrarily large number of states within the superposition". AG* > through successive interaction with other qubits, effectively growing > exponentially. > > > >> >> >>> all the while remaining in a super position (completely isolated from >>> the environment that contains the quantum computer) for the duration of the >>> computation. The computation might have been a very long one, and may have >>> involved vast numbers of states simultaneously held by the qubits during >>> the computation. Each of these states is designed by the quantum >>> computation to interfere in such a way to that in most of the branches the >>> measured qubits will yield the same result. >>> >>> We know we can prepare a quantum computation. We know we can measure the >>> qubits afterwards to get the final answer. >>> The big question of "what is going on in the middle?" can only be >>> answered by resorting to asking what the theory can tell us of what the >>> wave function is doing to perform and implement the computation while we >>> are not measuring it. >>> >> >> *Since when does QM tell us what is happening to a wf when the system it >> represents is not being measured? * >> > > This is given by the Schrödinger equation. > *Of course. Right; I was confused by what you were trying to describe. AG* > > >> >> *Are you referring to decoherence theory? AG * >> > > No. Decoherence is exactly what you want to avoid within a quantum > computer. That is the main engineering difficulty, keeping coherence > (keeping the system of the quantum computer isolated from the rest of the > environment so that the superposition can be maintained and evolve and > (from our point of view (being isolated from it)) enter many many states. > *If the superposition of a qubit evolves, all that can change are the probability amplitudes of its TWO components. Am I mistaken? AG * > > >> >>> If one denies the existence of the wave function >>> >> >> >> *I don't. AG * >> > > Okay. That's good. If one accepts that the wave function is real, and > that it can implement computations, > *How can a wf implement computations"? AFAIK, when expanded into orthogonal eigenstates, it can be use to calculate probabilities of each eigenvalue corresponding to each eigenvalue. I never heard it could do more than that. AG * > then the interesting question becomes: what happens when those > computations are conscious? > > Jason > > >> >> however, it leaves no room for talking about these intermediate states >>> that are necessary to explain how the final result of the computation ends >>> up in the qubits. >>> >>> Jason >>> >> -- >> 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] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at https://groups.google.com/group/everything-list. >> For more options, visit https://groups.google.com/d/optout. >> > > -- 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.
