On Wednesday, August 7, 2019 at 9:19:57 PM UTC-5, Brent wrote: > > > > On 8/7/2019 2:56 PM, Philip Thrift wrote: > > > > On Wednesday, August 7, 2019 at 2:59:04 PM UTC-5, Brent wrote: >> >> >> >> On 8/7/2019 11:15 AM, Philip Thrift wrote: >> >> >> If a multiplicity of somethings isn't present in a quantum computer, then >> how does the speedup occur? >> >> >> By not decohering at every bit flip and keeping the single state rotating. >> >> Brent >> > > > > > > Then how does an answer come out? > > > By decoherence at the end. > > > Brent > >
Well, sure. But there is still a multiplicity of somethings. Histories. https://pdfs.semanticscholar.org/39d9/11e25b835ce8d34910c0a9e02f22ef8d4c41.pdf : *In QMT a system is defined by a triple (Ω, A, D) where Ω is the set of* *histories, A is the event algebra and D is the decoherence functional. An event is a set of histories and the event algebra is the set of all events to which the theory assigns a measure. The event algebra is, then, a subset of the power set of Ω. * *The decoherence functional is a function with two arguments D : A × A → C such that* *• D(A, B) = D(B, A)* *∗ ∀ A, B ∈ A ;* *• For any finite collection of events A1, . . . , Am ∈ A, the m × m matrix* *Mab := D(Aa, Ab) is positive semi-definite ;* *• D(Ω, Ω) = 1 ;* *• D(A ∪ B, C) = D(A, C) + D(B, C) ∀ A, B, C ∈ A such that A ∩ B = ∅ .* *The quantum measure, µ(E), of an event E ∈ A is given by the diagonal of the decoherence functional D:* *µ(E) := D(E, E).* @philipthrift -- 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/ee3f2667-c56d-40ad-b2e7-8fa31b57f596%40googlegroups.com.
