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comment git rebase: why i have to resolve the same conflict over and over
yes, the solution was to never ever use rebase again. pull, merge and resolve with add is all that you should ever need
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comment Negative energy/mass bounds on de-Sitter spacetime
Another thing: "energy in cosmology is not conserved" is an statement that is true both on de-Sitter and Anti-de-Sitter cosmologies, but the lack of the energy-positiveness-theorem is specific to de-Sitter spaces, so I hope that you see that the former does not by itself explain the latter
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comment Negative energy/mass bounds on de-Sitter spacetime
but energy conservation as a constraint is a completely independent constraint on the system than energy positivity: energy conservation for non-gravitational fields is just the divergencelessness of $T_{\mu \nu}$, but energy positivity is about quantum inequalities and energy conditions.
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comment Negative energy/mass bounds on de-Sitter spacetime
"the total conserved energy can't be well-defined in our (nearly) de Sitter space" I'm not wondering about energy conservation, What I'm wondering is negative mass concentrations as would be expected if the positive-energy theorem does not hold. You seem to be conflating the issue of energy-conservation in GR (which as you rightly said, the lack of a Killing time vector means that it is absent) with that of negative energy. Why are both issues related?
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accepted Negative energy/mass bounds on de-Sitter spacetime
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comment Negative energy/mass bounds on de-Sitter spacetime
but I thought that was what the lack of a positivity theorem was implying: since our universe is de-Sitter, there is no such thing as a 'theorem' that forbids them. At least not a known one yet. Or is there some complementary non-negativeness theorem beyond the one being discussed here? You mention that it is forbidden because the vacuum "obviously" doesn't collapse and we are here :-) so, are you saying that the reason negative energy is not seen is purely anthropic?
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comment Negative energy/mass bounds on de-Sitter spacetime
thanks. What would you say that is the reason we haven't seen/detected negative energy/mass yet? Is it forbidden by some quantum/stringy symmetry? It is just a symmetry-breaking thing that could change if temperature gets to inflationary-epoch levels? Or maybe negative mass is composed of sterile/dark energy that doesn't interact with our sector?
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comment Negative energy/mass bounds on de-Sitter spacetime
thanks, that paper was the one that brought the question in my head in the first place :-)
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comment On the coordinate independence of general relativity
That hole argument still confuses the bejeezus out of me
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revised Negative energy/mass bounds on de-Sitter spacetime
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