Pluriharmonic function

In mathematics, precisely in the theory of functions of several complex variables, a pluriharmonic function is a real valued function which is locally the real part of a holomorphic function of several complex variables. Sometimes such a function is referred to as n-harmonic function, where n ≥ 2 is the dimension of the complex domain where the function is defined.[1] However, in modern expositions of the theory of functions of several complex variables[2] it is preferred to give an equivalent formulation of the concept, by defining pluriharmonic function a complex valued function whose restriction to every complex line is a harmonic function with respect to the real and imaginary part of the complex line parameter.

  1. ^ See for example (Severi 1958, p. 196) and (Rizza 1955, p. 202). Poincaré (1899, pp. 111–112) calls such functions "fonctions biharmoniques", irrespective of the dimension n ≥ 2 : his paper is perhaps[citation needed] the older one in which the pluriharmonic operator is expressed using the first order partial differential operators now called Wirtinger derivatives.
  2. ^ See for example the popular textbook by Krantz (1992, p. 92) and the advanced (even if a little outdated) monograph by Gunning & Rossi (1965, p. 271).