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We know the universe is expanding because of the red shift of far away galaxies, the further away the galaxies are the faster they recede. We also know that the energy in the universe (mass and other forms) will slows the expansion. If there is enough energy we will end up with the big crunch and if not enough, the slow death. (Please correct me if there is a fundamental error in the above)

So it seems to me that if there was less mass energy (or at least less than currently) in the universe then the the size (volume) of the universe would have been greater than it is due to the (Mass) energy it currently has ( ie a larger volume, 13 billion years after the big bang.)

Now if space ("the vacuum") has energy, (ie so and so joules per cubic meter,) then a larger volume would have a larger energy content. (assuming the same energy density of course.)

Assuming that energy can't be created or destroyed so that the total energy of the universe is constant ( maybe a dodgy assumption ...but anyway..) Then the total vacuum energy of the universe is less due to the matter and stuff in the universe than the vacuum energy would be if there was less matter and stuff in the universe. (assuming the energy density of the vacuum is the same in the two scenarios.).

But all the galaxies are receding from each other, so they are all ncreasing their kinetic energy (ie moving faster).

So on the one hand we have more kinetic energy (moving galaxies) and on the otherhand less vacuum energy (smaller volume due to the effects of mass/gravity)

So my question is, could mass somehow be converting the vacuum energy into the kinetic energy?

ie Kind of sucking space into mass which would cause effects similar to gravity , and of course, the moving space would give rise to different geometries of the space much like the different geometry of water flowing down a plughole vs when the plug is in place and as such "bends space" to give gravity ala general relativity.

andy
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Apparent velocity of distant galaxy is not real velocity, and its acceleration doesn't mean its real momentum has raised (no perceived pseudo-force in its referential, for instance): it is the space in between that have elongated. So it does not make sense to consider this as kinetics energy (or as the temperature of a "universe gas"). Indeed at a distance (= "event horizon") you would find that this energy is infinite. Or... considering the time compression, you could consider that its apparent clock is frozen, and consider various related energy measurements as null (e.g. through wavelength of radiations). And for greater distances, things no longer even make sense.

To wrap up, apparent velocity (or acceleration) of objects are not real properties of objects, and as such are not bounded by objects physical limits and equations (they can go faster that light as a shadow can, and you wouldn't consider the kinetic energy of a shadow as well ;-) ).

Fabrice NEYRET
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