Originally posted by sonhouse
In the case of black holes, they all eventually 'evaporate', becoming a white hole, thus restoring that particular cycle of energy that 'left' the universe and coming back in in the form of radiation. The only thing is, the tiny ones go fast, microseconds for the real small ones but the big ones, if they don't evaporate till eons after the life of the unive ...[text shortened]... ever it is death, then the black hole is still there with all its energy intact, what now?
I see black holes and the energy contained therein as being part of the universe, regardless of whether or not they can communicate directly with us. After all, we can detect their gravity can we not?
But your response doesn't answer my question as to whether the universe as a whole has any conservation of energy law.
Space is expanding, and this creates potential energy. Is there any reason to believe that this potential energy is being balanced by a loss of energy somewhere else?
If we had a rope between us and one of the galaxies that shows redshift due to the expansion of space, we could potentially use the ropes pull to power something.
It may seem an insignificant issue now, but in the early seconds of the big bang the energy release must have dominated the energy scene at the time.