"Paul Bramscher" wrote in message
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Is it possible that we have multiple big bangs, at perhaps the galactic
level

The phrase "Big Bang" refers specifically to the theory
describing the expansion of the space in which those
galaxies exist and shouldn't be confused with normal
explosions. It is possible to have multiple big bangs
but we are constrained to observing only one since we
are inside it. This paper talks about the possibility,
see in particular the simple diagram on page 11:

http://arxiv.org/abs/astro-ph/0301199

but not generally beyond this (never involving all available
matter/energy), and no singular beginning or end to all matter/energy,
but just a bunch of localized recycling?

That description would fit a supernovae, localised
recycling of a limited amount of matter and energy.
I'm sure you can think of other examples.

George