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arXiv · 1207.7107

A modified Yamabe invariant and a Hopf conjecture

Ezio Araujo Costa
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Abstract

In this paper we define the bi-orthogonal sectional curvature and we present two modified Yamabe invariants for compact 4-dimensional manifolds. In particular we obtained a relationship between one of these invariants and a Hopf conjecture.

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Ezio Araujo Costa. 2012-07-30. A modified Yamabe invariant and a Hopf conjecture. https://arxiv.org/abs/1207.7107

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