Positive scalar curvature on foliations

Abstract

We generalize classical theorems due to Lichnerowicz and Hitchin on the existence of Riemannian metrics of positive scalar curvature on spin manifolds to the case of foliated spin manifolds. As a consequence, we show that there is no foliation of positive leafwise scalar curvature on any torus, which generalizes the famous theorem of Schoen-Yau and Gromov-Lawson on the non-existence of metrics of positive scalar curvature on torus to the case of foliations.

Moreover, our method, which is partly inspired by the analytic localization techniques of Bismut-Lebeau, also applies to give a new proof of the celebrated Connes vanishing theorem without using noncommutative geometry.

Authors

Weiping Zhang

Chern Institute of Mathematics & LPMC, Nankai University, Tianjin 300071, P. R. China, and
Center for Applied Mathemtaics, Tianjin University, Tianjin 300072, P. R. China