- #1
Naty1
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I was looking for some information on the total energy in the universe:
Crowell said: How does conservation of energy apply to cosmology?
(oops. I lost the thread where this appeared...ok, post #12 here: https://www.physicsforums.com/showthread.php?t=453837&highlight=zero+energy+universe)
Yet I turned up this which seems to say it's zero:
http://arxiv.org/PS_cache/gr-qc/pdf/0605/0605063v3.pdf
(and Wikipedia...http://en.wikipedia.org/wiki/Zero-energy_universe)
ON THE ZERO-ENERGY UNIVERSE
Marcelo Samuel Berman1
We consider the energy of the Universe, from the pseudo-tensor point of view(Berman,1981).
We find zero values, when the calculations are well-done.The doubts concerning this subject are
clarified, with the novel idea that the justification for the calculation lies in the association of the
equivalence principle, with the nature of co-motional observers, as demanded in Cosmology. In
Section 4, we give a novel calculation for the zero-total energy result.
in which he says:
Are these views complementary or contradictory?
Crowell said: How does conservation of energy apply to cosmology?
General relativity doesn't have a conserved scalar mass-energy that can be defined in any spacetime.[MTW 1973] It only has certain definitions that work in special cases, including stationary spacetimes and asymptotically flat spacetimes. Cosmological solutions aren't stationary or asymptotically flat. Therefore there is no way to define the total energy of the universe (regardless of whether the universe is spatially finite or infinite). There is not even any way to define the total energy of the observable universe. There is no way to say whether or not energy is conserved during cosmological expansion.
(oops. I lost the thread where this appeared...ok, post #12 here: https://www.physicsforums.com/showthread.php?t=453837&highlight=zero+energy+universe)
Yet I turned up this which seems to say it's zero:
http://arxiv.org/PS_cache/gr-qc/pdf/0605/0605063v3.pdf
(and Wikipedia...http://en.wikipedia.org/wiki/Zero-energy_universe)
ON THE ZERO-ENERGY UNIVERSE
Marcelo Samuel Berman1
We consider the energy of the Universe, from the pseudo-tensor point of view(Berman,1981).
We find zero values, when the calculations are well-done.The doubts concerning this subject are
clarified, with the novel idea that the justification for the calculation lies in the association of the
equivalence principle, with the nature of co-motional observers, as demanded in Cosmology. In
Section 4, we give a novel calculation for the zero-total energy result.
in which he says:
(Guth, 1981), as an accelerated expansion of the Universe, immediately after the creation
instant,while the Universe, as it expands,borrows energy from the gravitational field to
create more matter. According to his description, the positive matter energy is exactly
balanced by the negative gravitational energy, so that the total energy is zero,and that
when the size of the Universe doubles, both the matter and gravitational energies also
double, keeping the total energy zero (twice zero).
It has been generally accepted that the Universe has zero-total energy. The first such claim, as far as the present author recollects, was due to Feynman(1962-3). Lately,
Berman(2006, 2006 a) has proved this result by means of simple arguments involving
Robertson-Walker’s metric for any value of the tri-curvature ( 0,−1, 1 ).
Are these views complementary or contradictory?
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