Cyclic actions and elliptic genera

英文摘要：

Let $M$ be a $Spin$-manifold with $S^1$-action and let $σ\in S^1$ be of finite order. We show that the indices of certain twisted Dirac operators vanish if the action of $σ$ has sufficiently large fixed point codimension. These indices occur in the Fourier expansion of the elliptic genus of $M$ in one of its cusps. As a by-product we obtain a new proof of a theorem of Hirzebruch and Slodowy on involutions.