Re: Antimatter in the universe? (was "A question about mirrors")

[Herb Schulz <herbs@INTERACCESS.COM>]

> In the late fifties P was shown to be violated in the famous
> experiment of Wu et al, as we've been reminded here. A decade later
> T was shown to be independently unsymmetrical in Nature, and by the
> "CPT theorem" (which, being a theorem, I assume is absolutely true)
> C must, therefore, not be a symmetry of Nature. Please correct any
> misconceptions that might be evident in what I've written. If C is
> not a symmetry of Nature (or, more properly, Natural law) then is
> there hope that one might observe the electromagnetic radiation from
> distant galaxies and discern some distinctive difference due to the
> type of matter of which the galaxy is composed?

Howdy,

My impression was that P, C and therefor T violation (assuming CPT is
conserved) are a consequence of the weak interaction; the
electromagnetic interaction (at least to the first or second order?)
conserves P, C and T.  If that is true then you shouldn't be able to
distinguish anti-matter and matter via electromagnetic radiation.
You'd have to use the weak interaction; e.g., looking at the
anti-neutrinos, etc., as you stated.

Good Luck,
--
Herb Schulz
(herbs@interaccess.com)