On 29 Apr 2011, at 04:03, Stephen Paul King wrote:

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Hi Bruno,But are machine semantics restricted to a position basis mode ofexpression?

`That was the question I as asking. Probably not, but I am not sure.`

`Even pure spin computations needs the use of position, at least for`

`reading and writing memories. But this might be a human limitation,`

`not a machine limitation.`

I can see how this would do damage claims of universality!

`Why? I don't see this at all. Remember that with comp the numbers are`

`only dreaming space and position. Such notion are secondary and`

`emerging from the numbers points of view.`

This is a open problem for me as well as my toy model is only framedin the position basis at the moment and I do not know how togeneralize it at the moment, but I have seen hints in the C* algebraduality of Gel’fand. arxiv.org/pdf/0812.3601 and www.mathstat.dal.ca/~p.l.lumsdaine/research/Lumsdaine-2009-Duality.pdfQM seems to demand that all possible basis be treated equally,there can be no preferred basis (via the linearity of the tensorproduct of Hilbert spaces?!); just as there can be no preferredreference frame in GR. http://www.physicsforums.com/showthread.php?t=362959and http://plato.stanford.edu/entries/qm-everett/

`Yes. I agree. There are no preferres basis, like they are no preferred`

`universal system. That is why I take the numbers.`

“The preferred basis problem is arguably a more serious problem fora splitting-worlds reading of Everett. In order to explain ourdeterminate measurement records, the theory requires one to choose apreferred basis so that observers have determinate records (ordeterminate experiences) in each term of the quantum-mechanicalstate as expressed in this basis. The problem is that not just anybasis will do this. Making the total angular momentum of all thesheep in Austria determinate by choosing such a preferred basis totell us when worlds split, would presumably do little to account forthe determinate memory I have concerning what I just typed. But thisis the problem, we do not really know what basis would make our mostimmediately accessible physical records, those records thatdetermine our experiences and beliefs, determinate in every world.The problem of choosing which observable to make determinate isknown as the preferred-basis problem.”

`There is no splitting, both with Everett and comp. Only relative`

`states. The 3-states are defined relatively to universal numbers., and`

`the 1-states are defined relatively to infinities of universal numbers`

`(the infinitely many competing below our substitution level).`

That we humans have a bias toward the position basis may verywell be an artifact of our physical senses. It is interesting tonote that bases exists that are combinations of other bases. Someresearch by Aharonov et al in the so called Weak Measurement areashows some unusual implications of this: http://en.wikipedia.org/wiki/Weak_measurementI suspect that the “basis problem” is just another version ofthe measure problem.

`I think there is no basis problem. All versions of it comes from a`

`too much literal understanding of the notion of world or universe`

`(which makes no sense with comp).`

`Also, I think that the measure problem in QM is mainly solved by`

`Gleason theorem. And the measurement problem is solved by Everett MW.`

`I might be wrong (if Weinstein is correct, for example). Comp is far`

`from being as clean as QM, though, but it should lead to QM, with`

`perhaps some modification, which might solve the remaining problems.`

Bruno http://iridia.ulb.ac.be/~marchal/ -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to everything-list@googlegroups.com. To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.