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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeJul 22nd 2011
    • CommentRowNumber2.
    • CommentAuthorTobyBartels
    • CommentTimeJul 23rd 2011

    Wow, I didn’t realise that the definition of globally hyperbolic was so simple!

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJul 23rd 2011

    Wow

    Yes, it is surprising that this is not advertized more widely.

    I have now added pointers to the theorems that establish this.

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeJul 23rd 2011

    I have expanded the discussion a bit more.

    • CommentRowNumber5.
    • CommentAuthorTobyBartels
    • CommentTimeJul 23rd 2011

    This theorem means that something that I wrote at Cauchy surface is not true; I fixed it in such a way as to link to globally hyperbolic (again) there.

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeJul 23rd 2011

    Currently the entry says that global hyperbolicity of XX implies the existence of a homeomorphism ×ΣX\mathbb{R} \times \Sigma \to X that exhibits the foliation by Cauchy surfaces.

    I should check: can we not assume that this is a diffeomorphism with respect to the canonical smooth structure?

    I don’t have more time for this right now. Maybe somebody knows directly? Otherwise I’ll try to check later.

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