An analytic characterization of the symmetric extension of a Herglotz-Nevanlinna function in several variables

Abstract

In this paper, we derive an analytic characterization of the symmetric extension of a Herglotz-Nevanlinna function in several variables. Here, the main tools used are the so-called variable non-dependence property and the symmetry formula satisfied by Herglotz-Nevanlinna function and Cauchy-type functions. We also provide an extension of the Stieltjes inversion formula for Cauchy-type functions.