C of L49...Maxwell 's Demon: a history

[Paul Cray]

The Demon also has to do work in order to open and shut the hole as well as
determine the trajectories of the fast moving molecules. It is interesting
that Maxwell says that though the Demon's faculties are "sharpened", its
attributes are as "essentially finite as our own." The Demon is bound by the
same Laws of Thermodynamics as any machine (non-biological or biological)
and it is a matter of determining whether or not the entropy increase
through the Demon doing the work to track the molecules and open and close
the hole is greater than the entropy decrease from separating the molecules.


Paul


2009/6/4 <malignd at aol.com>

> But it doesn't.  As has been pointed out, the Demon needs energy from
> without, in the form of light, to see.
>
>
>
> -----Original Message-----
> From: kelber at mindspring.com
> To: pynchon-l at waste.org
> Sent: Wed, 3 Jun 2009 5:20 pm
> Subject: Re: C of L49...Maxwell 's Demon: a history
>
>  Maxwell's Demon gets around the Second Law, thwarting entropy.  Is entropy(or
> its social analog,apathy) the "magic, anonymous and malignant, visited on her
> from outside and for no reason at all" that keeps Oedipa in her tower?  Then
> Tristero = Maxwell's Demon?
>
> Laura
>
> -----Original Message-----
> >From: Mark Kohut <markekohut at yahoo.com>
>
> >
> >
> >p. 86 hc...I won't link here to wikipedia or anything re JCMaxwell, you
> can....I just want to add the personal association of the bearded Victorian that
> he was with the bearded Smith Brothers of the famous coughdrops. (No P
> connection;  thanks for indulging me)
> >
> >He was raised and remained a VERY Christian-believing scientist and was
> anti-Darwin's theory.
> >
> >Maxwell is widely acknowledged as the nineteenth century scientist whose work
> had the greatest influence on twentieth century physics. His electromagnetic
> theory and its associated field equations 'paved the way for Einstein's special
> theory of relativity, which
>  established the equivalence of mass and energy.
> Maxwell's ideas also ushered in the other major innovation of 20th century
> physics, the quantum theory.  ----from an online bio, not wikipedia
> >
> >Maxwell's Demon---wikipedia:
> >Maxwell conceived a thought experiment as a way to explain the statistical
> nature of the second law. He described the experiment as follows[2]:
> >... if we conceive of a being whose faculties are so sharpened that he can
> follow every molecule in its course, such a being, whose attributes are as
> essentially finite as our own, would be able to do what is impossible to us. For
> we have seen that molecules in a vessel full of air at uniform temperature are
> moving with velocities by no means uniform, though the mean velocity of any
> great number of them, arbitrarily selected, is almost exactly uniform. Now let
> us suppose that such a vessel is divided into two portions, A and B, by a
> division in which there is a small hole, and that a being, who can see the
> individual molecules, opens and closes this hole, so as to allow only the
> swifter molecules to pass from A to B, and only the slower molecules to pass
> from B to A. He will thus, without expenditure of work, raise the temperature of
> B and lower that of A, in contradiction to the second law of thermodynamics.
> >
> >Schematic figure of Maxwell's demon
> >In other words, Maxwell imagines one container divided into two parts, A and B.
> Both parts are filled with the same gas at equal tempe
> ratures and placed next to
> each other. Observing the molecules on both sides, an imaginary demon guards a
> trapdoor between the two parts. When a faster-than-average molecule from A flies
> towards the trapdoor, the demon opens it, and the molecule will fly from A to B.
> The average speed of the molecules in B will have increased while in A they will
> have slowed down on average. Since average molecular speed corresponds to
> temperature, the temperature decreases in A and increases in B, contrary to the
> second law of thermodynamics.
> >
> >
> >
> >
>
>
>
> ------------------------------
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