For whatever its worth. David Deustch's solution to grandfather paradox eclipses this objection. Time travelers go back to a duplicate universe and kill grand dad, or Jack the Ripper, before he can do harm to the people in his lifespan. The travelers return to an unchanged world, but they did change reality in the universe next door. There's no reason why states cannot be duplicated as long as they don't violate Heisenberg's uncertainty rule. If we go back to Einstein's GR block universe/frame, you can copy anything in the past (light cone?) and duplicate it somewhere else. As long as you can glom past info, you can dupe it. Nothing with Einstein's GR, Heisenberg's Uncertainty, or Deutsches' Grand dad shot in another universe, prevents duping.
In Everett's MWI the mulitple "worlds" are just projections of the one state-of-the-multivers onto different (approximately) orthogonal subspaces. There's no duplicating of states. And in any case the no-cloning theorem doesn't prohibit there being multiple copies of a state, it just prevents you from measuring an unknown state completely so that you know you have duplicated it. You can make copies of a state you know (i.e. prepare). And you could coincidentally make a copy of an unknown state - you just wouldn't be able to know it was a copy. Brent -----Original Message----- From: meekerdb <[email protected]> To: everything-list <[email protected]> Sent: Sat, Apr 25, 2015 2:52 am Subject: Re: Practicalities of Mind Uploading On 4/24/2015 4:24 AM, LizR wrote: On 24 April 2015 at 23:03, spudboy100 via Everything List <[email protected]> wrote: How about this? MWI, if true, refutes the no-clonning conundrum. Yes, that's my opinion too - but it doesn't allow US to do it. The MWI is constantly duplicating quantum states, indeed there are infinite numbers of copies of the entire universe's quantum state waiting to differentiate. In Everett's MWI the mulitple "worlds" are just projections of the one state-of-the-multivers onto different (approximately) orthogonal subspaces. There's no duplicating of states. And in any case the no-cloning theorem doesn't prohibit there being multiple copies of a state, it just prevents you from measuring an unknown state completely so that you know you have duplicated it. You can make copies of a state you know (i.e. prepare). And you could coincidentally make a copy of an unknown state - you just wouldn't be able to know it was a copy. 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]. 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. -- 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.
