Thanks. I read it quickly. I didn't understand the details.
I have no really opinion. I have been more impressed by Freedman
analogical quantum machine, but Calude suggestion is of the same
type.  This could lead to a refutation of comp, not of Church
thesis imo. Those machine does really not compute digitally.
I am open to the idea that we will build them, but not tomorow!


>There was an article recently in New Scientist about a new way to geet
>computing beyond the "Turing barrier".  I think it is somewhat similar
>in spirit to the analog machines, in that it uses infinities, but it is
>based on the quantum computing model.  The NS article is reprinted at
> and the original
>paper is available at
>>From the NS article:
>    His suggestion is to think bigger: why not create a superposition
>    of every conceivable state at once? Something like a hydrogen atom
>    has infinitely many possible energy levels. While the levels start
>    out well-spaced, they get closer as the energies grow higher, until
>    they become almost indistinguishable. In a paper to be published
>    in the inaugural edition of MIT's new journal Quantum Information
>    Processing, Calude and Pavlov have shown that a superposition of an
>    infinite number of energy states would allow a quantum computer to
>    do things no classical computer can ever manage-almost like running
>    "forever" in a finite time.
>    This leap means that a quantum computer can overcome Turing's most
>    famous barrier to computing power: the "halting problem".
>    ...
>    Calude is extremely proud of this result: he believes it could be
>    implemented on a real-life quantum computer, laying much that is
>    "unknowable" open to attack. "Using infinite superpositions is rather
>    theoretical, but not necessarily non-practical or non-testable,"
>    he says.
>My opinion is that infinite superpositions will never be practical hence
>his machine is of only theoretical interest.

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