Estimates of solutions for degenerate elliptic equations of second order§

Abstract

This article deals with some boundary value problems for elliptic equations with degenerate rank 0, mainly the mixed problem. We first give the formulation of the problem, and then the estimates of solutions, which can be used to prove that solutions to the above problem exist. In this article, we use the complex method, i.e., first discuss the corresponding problem for degenerate elliptic complex equations of first order, and later discuss the above problem for the degenerate elliptic equations of second order. §Dedicated to Professor Guochun Wen on the occasion of his 75th birthday.