# Tag Info

### The convex hull of a manifold whose cobordism class is trivial

Implicit in the other responses is the fact that if $M$ bounds a convex manifold $W$, then $W$ is contractible and so M has the homology of a sphere. So any null-cobordant manifold that is not a ...
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Accepted

### Isometry between Minkowski space and Tangent space in an article by Stefan Waldmann

I think you are confused by two different uses for the word "isometry". There is first the notion of a linear isometry between vector spaces equipped with a non-degenerate bilinear form. ...
• 7,513
Accepted

### Concrete descriptions of $S^1$-bundles over smooth manifold $Y$ underying a K3 surface

You can say a fair amount about the topology of the total spaces of the different bundles, although I suspect none of them is a particularly well-known manifold that has a `name'. (Except of course ...
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