p6 wrote:
What's more likely. A Big Bang where everything starts from
a singularity or M-theory Big Splat (ekpyrotic scenerio)
where two higher dimensional colliding branes produced
the matter and energy in our universe??

Note that researchers said the two produced the same
result. We are mostly familiar with Big Bang where the
entire universe before inflation is just planck size.
Another model called Big Splat or ekpyrotic scenerio can
also cause the flatness of the horizon and space and
results in microwave background radiation too due to
the recombination of nuclei and electrons that released
the radiation and the responding expanding of space
causing the gamma rays and other higher rays to slowly
turn to microwave.

I think Big Splat (ekpyrotic scenerio) is more likely
than a Big Bang (which is a bit way off). What do you
think?

p6

Yes.
Unfortunately that's the best answer science has...for the moment.

Shawn