Morse index of free boundary disk for pseudoconvex domain

Abstract

In this paper we study the Morse index for the $\overline{\partial}$-energy of a non-holomorphic disk in a strictly pseudoconvex domain in $\mathbb{C}^n$ or in a K\"ahler manifold with non-negative bisectional curvature. We give a proof that a $\overline{\partial}$-energy minimizing disk is holomorphic; in fact, more generally we show that a non-holomorphic critical disk for the $\overline{\partial}$-energy has Morse index at least $n-1$. We also extend the result to domains which satisfy the weaker $k$-pseudoconvexity property for $k\geq 2$.