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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: Thu, 23 Jun 2005 04:34:30 +0000 UTC
Newsgroups: sci.astro.amateur
Just a couple of small comments.

Chris L Peterson wrote:
> The problem is that you are trying to apply concepts that stop making
> sense when taken to relativistic limits. What does it mean to take
> something with zero mass and multiply it by infinity? That's where
> quantum mechanics steps in and provides a better way of analyzing these
> things.

Once you bring in photons, of course, you've implicitly introduced
quantum mechanics to some degree.

> But photons always travel at c, regardless of the observer's frame. Two
> photons will each see the other traveling at c. There is no frame of
> reference that allows you to observe a photon at rest. This seems
> unintuitive, of course, since the things around us don't behave that
> way. But in the quantum realm, it's different. You need to trust the
> math to describe reality there.

Other than being photons, the bit about photons always "seeing" each
other moving at c is not a QM issue.  It is already a consequence of
the classical theory of relativity.

Brian Tung <brian@xxxxxxx>
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