Did you come accross a calculation of the entropy of
pre-big-bang medium? E.g. the stuff that exploded?
There have been calculations of the entropy of the
black-hole surface, so why not the big-bang-medium?

I know that the first pico-seconds of the big-bang
have been analysed and modeled in quite some detail by
cosmologists, in particular based on the background radiation
data. But is it possible to trace the entropy of this first pico-second
stuff down to the moment zero?
Besides, another related topic - is the entropy of the universe
increasing as it expands? What is the increase rate? Is there any
calulations of the entropy of present universe? This again comes down to
tracing this entropy increase and probably extrapolating it back to time
zero.

Regards,
Evgenij