Re: Galaxies and antimatter

Ray Johnstone wrote: 
On Mon, 23 May 2005 03:36:06 GMT, Sam Wormley <swormley1@xxxxxxxxx>
wrote:


Ray Johnstone wrote:

What is the evidence that other galaxies are made of matter rather
than antimatter? 

 Physics FAQ --
   http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/baryogenesis.html


Thanks, but what I don't follow (from your quoted URL) is

Essentially, causality prevents the separation of large chucks of
antimatter from matter fast enough to prevent their mutual
annihilation in the early universe. 

  Based on observation (no signature of annihilation energies expected
  with "large chuck" of antimatter), and observed asymmetry in particle
  decay times for matter and antimatter, it is a reasonable assumption
  that almost all the matter occurring in the Big Bang was annihilated
  early on. What we see about us is the matter that was "left over" after
  those annihilations.


.

Relevant Pages

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