- #1
g_mogni
- 48
- 0
Hello,
I have a very basic question about the expansion of the Universe and it could be that I'm being very stupid here: if the universe is expanding into the empty surroundings as the red shift evidence seems to demonstrate, then surely the universe must be doing work on the surroundings like a gas expanding freely against a massless piston. However we also know that the universe is likely flat and therefore has zero internal energy which is constant with time. According to the first law of thermodynamics we therefore have Delta U = 0 = W + Q, where W is negative since work is being done by the system (the universe) against the surroundings... does that mean that there is a positive heat (Q) entering the system from the surroundings? In that case how can heat come from the void region around the universe which has no energy whatsoever??
Thanks,
Gabriele Mogni
I have a very basic question about the expansion of the Universe and it could be that I'm being very stupid here: if the universe is expanding into the empty surroundings as the red shift evidence seems to demonstrate, then surely the universe must be doing work on the surroundings like a gas expanding freely against a massless piston. However we also know that the universe is likely flat and therefore has zero internal energy which is constant with time. According to the first law of thermodynamics we therefore have Delta U = 0 = W + Q, where W is negative since work is being done by the system (the universe) against the surroundings... does that mean that there is a positive heat (Q) entering the system from the surroundings? In that case how can heat come from the void region around the universe which has no energy whatsoever??
Thanks,
Gabriele Mogni