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Re: The beginning of space-based light pollution?

Subject: Re: The beginning of space-based light pollution?
From: Brian Tung
Date: Wed, 22 Jun 2005 23:43:53 +0000 UTC
Newsgroups: sci.astro.amateur
Mike Kreuzer wrote:
> OK, out of all this, this is the bit I still don't get.  Maybe I didn't go 
> the day this was explained in high school or something, but isn't momentum = 
> mass * velocity?  So no mass, no momentum?

That's the Newtonian definition ("quantity of motion is equal to quantity
of matter and velocity conjointly").  In a relativistic world, it isn't a
valid definition, and has to be supplanted by the Planck formula.

Brian Tung <brian@xxxxxxx>
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