On the $L^p$ index of spin Dirac operators on conical manifolds

Abstract

We compute the index of the Dirac operator on spin Riemannian manifolds with conical singularities, acting from $L^p({\Sigma }^{+})$ to $L^q({\Sigma }^{-})$ with $p,q>1$. When $1+\frac{n}{p}-\frac{n}{q}>0$ we obtain the usual Atiyah-Patodi-Singer formula, but with a spectral cut at $\frac{n+1}{2}-\frac{n}{q}$ instead of 0 in the definition of the eta invariant. In particular we reprove Chou's formula for the $L^2$ index. For $1+\frac{n}{p}-\frac{n}{q}\le 0$ the index formula contains an extra term related to the Calderón projector.

17 pages, no figures