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Re: Old Stars





So somebody please tell me why the sky is dark -- in view of this discussion
about "Old Stars, quasars, and Q's flashlight. And in view of this
discussion, please tell me what importance the dark sky has.

The sky is dark because the universe is young. We therefore have a
horizon distance and objects beyond that distance have not had
sufficient time for their light to reach us. The importance of
Olbers' paradox, then, is that it is direct evidence that the
universe has a finite age so we can only see a finite amount of
stuff. The first person to ever hit on basically this idea was Edgar
Allen Poe in "Eureka! A Prose Poem." There is a nice book on the
subject by Edmund Harrison called Darkness At Night.


I think this is the same question as "Why can we now see background
radiation?", but what do *I* know?


Not quite since the background radiation has always filled up the
entire universe -- every bit of the universe was hot and so every bit
emitted light. We see the radiation from the bits (relatively) near
us.



Paul J. Camp "The Beauty of the Universe
Assistant Professor of Physics consists not only of unity
Coastal Carolina University in variety but also of
Conway, SC 29526 variety in unity.
pjcamp@csd1.coastal.edu --Umberto Eco
pjcamp@worldnet.att.org The Name of the Rose
(803)349-2227
fax: (803)349-2926