Rigidity of non-negatively curved metrics on open five-dimensional manifolds

Valery Marenich

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arXiv · math/0411632

Rigidity of non-negatively curved metrics on open five-dimensional manifolds

Valery Marenich

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Abstract

As the first step in the direction of the Hopf conjecture on the non-existence of metrics with positive sectional curvature on $S^2 \times S^2$ D.Gromoll and K.Tapp in [GT] suggested the following (Weak Hopf) conjecture (on the rigidity of non-negatively curved metrics on $S^2 \times R^3$): "The boundary $S^2\times S^2$ of the $S^2 \times B^3\subset S^2 \times R^3$ with an arbitrary complete metric of non-negative sectional curvature contains a point where a curvature of $S^2 \times S^2$ vanish". In this note we verify this.

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Valery Marenich. 2004-11-29. Rigidity of non-negatively curved metrics on open five-dimensional manifolds. https://arxiv.org/abs/math/0411632

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