English

Connecting $H^\infty$-functional calculus and isometric dilations for commuting families of Ritt$_E$ operators

Functional Analysis 2026-06-26 v1

Abstract

Let (T1,,Td)(T_1,\ldots,T_d) be a commuting dd-tuple of RittE_E operators on some UMD Banach space XX. We show that (T1,,Td)(T_1,\ldots,T_d) admits a bounded HH^\infty-functional calculus if and only if TkT_k is an RR-RittE_E operator for every k=1,,dk=1,\ldots,d, and the dd-tuple (T1,,Td)(T_1,\ldots,T_d) admits an isometric dilation (U1,,Ud)(U_1,\ldots,U_d) on some UMD Banach space YY such that (U1,,Ud)(U_1,\ldots,U_d) is polynomially bounded. In the case where XX further possesses property (α)(\alpha), we establish other characterizations of the HH^\infty-functional calculus property for (T1,,Td)(T_1,\ldots,T_d) in terms of isometric dilations.

Keywords

Cite

@article{arxiv.2606.28214,
  title  = {Connecting $H^\infty$-functional calculus and isometric dilations for commuting families of Ritt$_E$ operators},
  author = {Christian Le Merdy and M. N. Reshmi},
  journal= {arXiv preprint arXiv:2606.28214},
  year   = {2026}
}