3
Main Tests of the Big Bang
•Hubble Expansion (not a test really, inspiration)
•Cosmic Microwave Background
•Abundance of light elements

Refinements of Big Bang Still Being Tested
–Possible “cosmological constant”
–Very early history:
•particle/antiparticle asymmetry
•“inflation” -- Details of very early very rapid expansion
•small r, T fluctuations which lead to galaxies
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