Remark about scalar curvature and Riemannian submersions

Lott, John

doi:10.1090/S0002-9939-07-08852-1

Remark about scalar curvature and Riemannian submersions
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by John Lott

Proc. Amer. Math. Soc. 135 (2007), 3375-3381

DOI: https://doi.org/10.1090/S0002-9939-07-08852-1

Published electronically: June 20, 2007

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Abstract:

We consider modified scalar curvature functions for Riemannian manifolds equipped with smooth measures. Given a Riemannian submersion whose fiber transport is measure-preserving up to constants, we show that the modified scalar curvature of the base is bounded below in terms of the scalar curvatures of the total space and fibers. We give an application concerning scalar curvatures of smooth limit spaces arising in bounded curvature collapses.

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