The linearized Calder\'on problem on complex manifolds

TL;DR

This paper proves that on certain complex manifolds, products of harmonic functions are complete, enabling solutions to the linearized Calderón problem even in cases where standard methods fail, by constructing Morse holomorphic functions.

Contribution

It extends the linearized Calderón problem solution from Riemann surfaces to higher-dimensional complex manifolds using Morse holomorphic functions.

Findings

Products of harmonic functions form a complete set on certain complex manifolds.

The method applies to manifolds without limiting Carleman weights.

Extends previous results from Riemann surfaces to higher dimensions.

Abstract

In this note we show that on any compact subdomain of a K\"ahler manifold that admits sufficiently many global holomorphic functions, the products of harmonic functions form a complete set. This gives a positive answer to the linearized anisotropic Calder\'on problem on a class of complex manifolds that includes compact subdomains of Stein manifolds and sufficiently small subdomains of K\"ahler manifolds. Some of these manifolds do not admit limiting Carleman weights, and thus cannot by treated by standard methods for the Calder\'on problem in higher dimensions. The argument is based on constructing Morse holomorphic functions with approximately prescribed critical points. This extends results of Guillarmou and Tzou (Duke Math. J. 2011) from the case of Riemann surfaces to higher dimensional complex manifolds.