Qiaochu Ma - Small Scale Index Theory, Scalar Curvature, and Gromov’s Simplicial Norm @IhesFr

Uploaded November 2025 | Updated September 2026, 2 weeks ago

Scalar curvature encodes the volume information of small geodesic balls within a Riemannian manifold, making it, to some extent, the weakest curvature invariant. This raises a natural question: what topological constraints does scalar curvature impose on manifolds? In this talk, we shall show that for a manifold with a scalar curvature lower bound (possibly negative), the simplicial norm of the Poincaré dual of the A-hat class can be controlled. This is joint work with Guoliang Yu.

Qiaochu Ma (Texas A&M)

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Find this and many more scientific videos on carmin.tv - a French video platform for mathematics and their interactions with other sciences offering extra functionalities tailored to meet the needs of the research community.

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Qiaochu Ma - Small Scale Index Theory, Scalar Curvature, and Gromov’s Simplicial Norm

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