From: John K Clark (johnkc@well.com)
Date: Fri Sep 06 1996 - 11:16:55 MDT
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On Thu, 5 Sep 96 hanson@dosh.hum.caltech.edu (Robin Hanson) Wrote:
>Dyson's derivation [for life in an open universe] was
>assuming you kept exactly the same hardware
That doesn't seem like a realistic assumption to me. In an open universe
everything will keep getting colder and most things will get larger and
weaker too. Life will have to keep adapting to new conditions.
>No need to spread out the hardware over trillions of light
>years
A heat engine will have to exploit very tiny differences in temperature and
will be very inefficient as a result. To get a usable energy output it would
need to be HUGE.
All electromagnetic photons would be of VERY low energy and so would have to
have an enormous wavelength. A simple quarter wavelength antenna for a
billion mile photon, or a billion light year one, would need to be
astronomical, and then some. A reflector to concentrate the photons for
energy use would be MUCH larger still.
John K Clark johnkc@well.com
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