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

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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