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Thread: a dispute over FLRW and inhomogeneities

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    Default a dispute over FLRW and inhomogeneities



    Green and Wald long ago showed convincing results (I was convinced) that the homogeneity and isotropy of the FLRW metric for cosmology in GR had the nice property that local inhomogeneities averaged out: there is no significant effect or interaction between the local solution of GR and the global solution. this allows you to solve structure formation with a local approximate solution on a large scale FLRW background.

    here are some folks challenging that view with an arXiv link embedded.

    The Universe is inhomogeneous. Does it matter? | CQG+

    i'm skeptical. the argument has the flavor of mathematical precision that might not be physically meaningful. others, including "you know who" are more open minded.

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    Default Re: a dispute over FLRW and inhomogeneities

    lol.
    who is you know who?
    Hawking?
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    Default Re: a dispute over FLRW and inhomogeneities

    oh, are her initials S H?
    lol
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    Default Re: a dispute over FLRW and inhomogeneities

    Stephen Hawking has too much to do with advancing his information paradox research to worry about this. he has never criticized the Green and Wald approach to averaging out local inhomogeneities over the FLRW metric.
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