Reply to Pedro Marijuan
Dear Pedro,
a). Bilogical information and QI. I really like your analogy between BI
and QI, especially remark on \"some brief biological windows\" in which
biological computing is possible. In the same way we have \"some brief
quantum windows\" in that quantum computing is possible. In April I had a
course of lectures at Institute of Physical Technologies of Russian
Academy of Sc. There is a strong group which works on quantum computers
with ion-registers. They pointed out to tremendous difficulty in
creation of long strings of ion-registers. Difficulties icreases
essentially nonlinear with increasing of the number of ions. Strings of
ions become very unstable. And \"brief quantum windows\" are too brief to
perform a quantum computational cycle. On the other hand, in QM such
composed systems are described very well by tensor products of Hilbert
spaces. During an informal conversation experimenters even presented
doubts that everything is okey with QM-description or at least our
understanding of it.
b). Not so many quantum algorithms. There is some analogy with
Analogous Computers. Such a physical divice is constructed for solution
of one of a restricted class of problems. Problems from teh
corresponding class can be solved essentially quicker than by digital
computers. An Analogous Computer works directly with physical
information without it digitalization. Are quantum computers special
Analogous Computers? In some sense yes. Therefore it is not so
surprising that we can solve only very special problems. But of course,
such an analogy might be totally wrong.
Reply to Michael Devereux:
a) Conference proceedings of Vaxjo conferences, see about these
conferences at http://www.vxu.se/msi/aktuellt/konferens/index.xml
can be received without any charge if you send me Email, with subject
Proceedings and your post-address (except the last two years, since
American Institute of Physics started to publish the proceedings of our
series of conferences).
b). Interpretation of wave function.
Michael: \"I’m convinced that Born got the interpretation of the
wavefunction correct. Quantum theory, as you emphasize, Andrei, is
fundamentally about probability - the probable result of the next
measurement. One mistake, and an almost ineradicable source of
confusion, is the misunderstanding that the wavefunction, Psi, can also
always be the present state of the physical system. One can cite real
examples where both interpretations are not possibly valid
simultaneously.I’ve traced the mistaken notion that Psi is always the
state of the system as far back as Bohm’s book on quantum mechanics.
(Does anyone know an earlier source?) He certainly doesn’t even attempt
a proof, merely citing some special cases.\"
Dear Michael,
I agree with you that interpretation of wave function is the basic
problem of QM. The presence of numerous interpreation and the
impossibility to choose one of them (\"to prove\" that this one is correct
and all others are not) expresses the deepest crises in physics.
\"The wavefunction, Psi, can also always be the present state of the
physical system.\" -- This is nothing else than the conventional
Copenhagen interpretation of wave function -- Bohr and Heisenberg, von
Neumann, Pauli,... The story was very complicated. They chosen such an
interpretation not with the great pleasure. There was a lot of doubts.
Personally I completely agree with you. I do not think that the
Psi-function can be always considered as the state of e.g. individual
electron. For stationary states - yes, but nonstationary?
With Best Regards,
Andrei Khrennikov
Director of International Center for Mathematical Modeling in Physics,
Engineering, Economy and Cognitive Sc.,
University of Vaxjo, Sweden
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Received on Sat May 20 22:53:04 2006
