On 24 April 2015 at 11:27, Bruce Kellett <[email protected]> wrote: > LizR wrote: >> >> >> But there's no-cloning to consider - plus whether a simulated quantum >> state is the same as a real one... > > > No-cloning of an unknown quantum state is simply the statement that there is > no unitary operator that will enable you to transfer the properties of one > unknown quantum state to another.
> Simulating a quantum state might be another matter. Quantum states are > generally described in terms of some basis in Hilbert space. The > coefficients of the expansion in that basis are arbitrary complex numbers, > subject to the usual normalization conventions for the state. If you want to > simulate this state, you have to simulate these coefficients to arbitrary > precision. This is not possible in finite time with a digital computer. > However, if an infinite number of calculations are routinely possible for a > Turing machine in Platonia, then who knows? > > I will give my proof that these coefficients are indeed dense in the complex > plane at a later time, if required. The inability to clone a particular quantum state at will does not mean a copy of the quantum state cannot exist, and in fact in a large enough universe it will exist, without anyone putting any effort into creating it. But it is unreasonable to insist that a copy of a brain must be identical to the quantum level when in ordinary life our brains undergo gross (compared to the quantum level) changes, and we feel that we survive. -- Stathis Papaioannou -- 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.
