English

The $H^\infty$-functional calculus for right slice hyperholomorphic functions and right linear Clifford operators

Spectral Theory 2025-05-06 v1

Abstract

In 2016, the spectral theory on the SS-spectrum was used to establish the HH^\infty-functional calculus for quaternionic or Clifford operators. This calculus applies for example to sectorial or bisectorial right linear operators TT and left slice hyperholomorphic functions ff that can grow as polynomials. It relies on the product of the two operators e(T)1e(T)^{-1} and (ef)(T)(ef)(T), both defined via some underlying SS-functional calculus (also called ω\omega-functional calculus). For left slice holomorphic functions ff this definition does not depend on the choice of the regularizer function ee. However, due to the non-commutative multiplication of Clifford numbers, it was unclear how to extend this definition to right slice hyperholomorphic functions. This paper addresses this significant unresolved issue and shows how right linear operators can possess the HH^\infty-functional calculus also for right slice hyperholomorphic functions.

Keywords

Cite

@article{arxiv.2505.02783,
  title  = {The $H^\infty$-functional calculus for right slice hyperholomorphic functions and right linear Clifford operators},
  author = {Fabrizio Colombo and Francesco Mantovani and Peter Schlosser},
  journal= {arXiv preprint arXiv:2505.02783},
  year   = {2025}
}
R2 v1 2026-06-28T23:21:42.966Z