> Relativity allows some physical distributions of stress-energy to pick out a meaningful set of coordinates.
More precisely, with certain distributions of stress-energy, computations become much simpler in particular coordinates. But that does not mean the coordinates have any physical meaning. If there are any actual invariant properties of the spacetime that particular coordinates make more evident, those properties can always be expressed in coordinate-independent terms, for example in terms of Killing vector fields.
More precisely, with certain distributions of stress-energy, computations become much simpler in particular coordinates. But that does not mean the coordinates have any physical meaning. If there are any actual invariant properties of the spacetime that particular coordinates make more evident, those properties can always be expressed in coordinate-independent terms, for example in terms of Killing vector fields.
> (as has been known in cosmology for many years. cf. <https://arxiv.org/abs/1211.6338> ยง2 notably p 4)
I don't see anything in that paper that supports any claim stronger than the one I agreed to above. If you think you do, please give a specific quote.