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Results tagged with spherical-geometry
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user 15743
21
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For which $b$ it is possible that $S^n$ can have a Lorentz metric? Why?
I would just like to point out that a slightly more general version of the statement in Moroianu's answer holds:
A compact orientable manifold $M$ admits a Lorentzian metric if and only if $\chi(M)=0 …
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