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arXiv · 0909.2208

A Note on the Topology of a Generic Subspace of Riem

Henrique de A. Gomes
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Abstract

For Riem(M) the space of Riemannian metrics over a compact 3-manifold without boundary $M$, we study topological properties of the dense open subspace Riem'(M) of metrics which possess no Killing vectors. Given the stratification of Riem(M), we work under the condition that, in a sense defined in the text, the connected components of each stratum do not accumulate. Given this condition we find that one of the most fundamental results regarding the topology of Riem(M), namely that it has trivial homotopy groups, would still be true for Riem'(M). This would make the topology of Riem'(M) completely understood. Coupled with the fact that for Riem'(M), we have a proper principal fibration with the group of diffeomorphisms, which makes Riem'(M)/Diff(M) a proper manifold (as opposed to Riem(M)/Diff(M)), we would have that the homotopy groups of the quotient are given by the homotopy groups of Diff(M), which reflects the topology of $M$. These results would render the space of metrics with no symmetries subject to the above condition, as an ideal setting for geometrodynamical analysis.

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Henrique de A. Gomes. 2009-09-11. A Note on the Topology of a Generic Subspace of Riem. https://arxiv.org/abs/0909.2208

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