Quarantine essay
Greg Egan
novel _Quarantine_ is now online:
http://www.gregegan.net/QUARANTINE/QM/QM.html
On a related matter, there's a great article by Scott Aaronson, "The
Limits of Quantum Computers", in the current Scientific American.
More on this at:
http://scottaaronson.com/blog/?p=309
It was Scott who pointed out to me a theorem proved in 1995 that
rendered most of _Quarantine_ impossible. The Scientific American
article is a good antidote to a number of common misconceptions about
quantum computers (including some to which, alas, _Quarantine_ fell
prey).
Gene Ward Smith
056e-44bf-8c0...@e10g2000prf.googlegroups.com:
> An essay I promised long ago describing the flaws in the
physics in my
> novel _Quarantine_ is now online:
Even hard sf isn't supposed to be perfect, or at least it
won't be. You did a magnificent job of getting the reader
completely buffaloed, and that's the point, isn't it?
But maybe I missed the point.
Greg Egan
> Greg Egan <grege...@netspace.net.au> wrote in news:738bfd22-
> 056e-44bf-8c01-0a33843f8...@e10g2000prf.googlegroups.com:
>
> > An essay I promised long ago describing the flaws in the
> physics in my
> > novel _Quarantine_ is now online:
>
> Even hard sf isn't supposed to be perfect, or at least it
> won't be. You did a magnificent job of getting the reader
> completely buffaloed, and that's the point, isn't it?
>
> But maybe I missed the point.
It was part of the point, and I'm not saying that these flaws render
_Quarantine_ worthless as a work of SF. I certainly knew when I was
writing the book that it was utterly implausible. But I wasn't aware
of *quite* how many things I was getting wrong -- and in particular,
one theorem which was proved a few years after the book was published
really drives a stake through its heart. I think it's worth letting
readers know about that result, since it goes well beyond (and in a
sense is independent of) the most *obviously* unlikely aspects of the
book (i.e. the human brain collapsing the wave function).
Richard Kennaway
> It was part of the point, and I'm not saying that these flaws render
> _Quarantine_ worthless as a work of SF. I certainly knew when I was
> writing the book that it was utterly implausible. But I wasn't aware
> of *quite* how many things I was getting wrong -- and in particular,
> one theorem which was proved a few years after the book was published
> really drives a stake through its heart. I think it's worth letting
> readers know about that result, since it goes well beyond (and in a
> sense is independent of) the most *obviously* unlikely aspects of the
> book (i.e. the human brain collapsing the wave function).
Where does that leave "Singleton", in which someone invents a device to
collapse the wave function, out of existential depair at the idea that
without collapse, no decisions ever mean anything?
--
Richard Kennaway
Greg Egan
(Richard Kennaway) wrote:
The device in "Singleton" doesn't collapse the wave function. What it
does, in effect, is run your mind on a classical computer despite
operating in a quantum-mechanical world; that's a different, and much
easier, problem than trying to collapse things in your environment.
Paul Benioff showed in the '80s that it's possible to build a
classical computer in a quantum world (and not just in the trivial
sense that a desktop computer *appears* to behave like a classical
computer).
In _Quarantine_ the protagonist could throw a pair of dice and
guarantee that he'd get two sixes, by collapsing the wave of himself
and his immediate environment. In "Singleton", if the protagonist's
robot daughter threw a pair of dice she'd still be split into versions
who saw all possible outcomes -- but if someone asked her to pick a
number from 1 to 12, she would give a unique answer. To be able to do
that, she doesn't have to collapse anything; her brain is a quantum
computer simulating a classical computer, and it's shielded from
interacting with the outside world until it reaches the endpoint of
its calculation of her unique choice of number.
Damien Sullivan
>http://www.gregegan.net/QUARANTINE/QM/QM.html
>
>On a related matter, there's a great article by Scott Aaronson, "The
>Limits of Quantum Computers", in the current Scientific American.
>More on this at:
>
>http://scottaaronson.com/blog/?p=309
Thank you! Good to know.
>It was Scott who pointed out to me a theorem proved in 1995 that
>rendered most of _Quarantine_ impossible. The Scientific American
Heh. The drawback of cutting-edge diamond hard ScF.
-xx- Damien X-)
Joseph Nebus
>Greg Egan <greg...@netspace.net.au> wrote:
>>http://www.gregegan.net/QUARANTINE/QM/QM.html
>>
>>On a related matter, there's a great article by Scott Aaronson, "The
>>Limits of Quantum Computers", in the current Scientific American.
>>More on this at:
>>
>>http://scottaaronson.com/blog/?p=309
>Thank you! Good to know.
Belatedly, I'd like to note that I'm glad for the essay too,
since I'd always felt like I was missing something about quantum
computers before and now I'm a bit more confident that the part which
I feel like I'm missing is the part which everybody is missing. At
least I think I have that right.
>>It was Scott who pointed out to me a theorem proved in 1995 that
>>rendered most of _Quarantine_ impossible. The Scientific American
>Heh. The drawback of cutting-edge diamond hard ScF.
Yeah, but at least the book was really cool.
--
Joseph Nebus
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