On Sun, 16 Jul 2000 21:20:37 -0700 (PDT)
"Robert J. Bradbury" <firstname.lastname@example.org>
>Katherine is one of the leading theoretical physicists
>in this area. To quote her conclusions:
>1) Nonbaryonic dark matter in our Galaxy seems to be required, and
>(I freely grant this point, but suspect if my perspective on
>the activities of intelligent technological civilizations turns out
>to be true, then this point may need to be reexamined.)
Robert, don't you mean that you *don't* freely grant this point, *except*
insofar as it is premised on natural cosmic evolutionary processes
unmodified by purposeful intelligent intervention (ie your perspective)?
I also noticed in the paper--which I read but was at some pains to
decipher-- that brown dwarfs were ruled out because of some experimentally
observed TeraV gamma rays. These TeraV gamma rays would not--so the theory
goes--be there if brown dwarfs with their accepted IR output populated the
halo in numbers sufficient to account for the dark matter mass. As I
understood it, the TeraV gamma rays are consumed in an interaction with the
IR photons that produces electron/positron pairs.
This point, plus other bits and pieces of the observed IR radiation
abundance--the low level of IR, actually--also suggests to me that the dark
matter is not composed of large numbers of matrioshka brains. If it were
matrioska brains *harvesting* the stellar output in an orderly fashion, and
then radiating away the waste heat, this would also result in infrared
emissions able to interfere with the TeraV gammas.
The issue of the lack of IR radiation plus the dark matter business leads
me to a question I've been mulling over. Could advanced civilizations halt
the unbridled stellar fusion and save the fuel for a more orderly regime of
consumption? (Is this anything like the *star lifting* business that I've
heard about?) This seems to me to combine the observed features of
substantial quantities of dark mass and low IR emissions, while still
allowing the matter in question to be baryonic rather than something exotic.
Hope I'm not embarrassing myself.
Best, Jeff Davis
"Everything's hard till you know how to do it."
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