Rigidity for the spectral gap on $RCD(K,\infty )$-spaces

Nicola Gigli, Christian Ketterer, Kazumasa Kuwada +1

We consider a rigidity problem for the spectral gap of the Laplacian on an $RCD(K,\infty )$-space (a metric measure space satisfying the Riemannian curvature-dimension condition) fo…