English

Isomorphisms of Hilbert C*-Modules and $*$-Isomorphisms of Related Operator C*-Algebras

funct-an 2025-05-08 v1 Operator Algebras

Abstract

Let M\cal M be a Banach C*-module over a C*-algebra AA carrying two AA-valued inner products <.,.>1< .,. >_1, <.,.>2<.,. >_2 which induce equivalent to the given one norms on M\cal M. Then the appropriate unital C*-algebras of adjointable bounded AA-linear operators on the Hilbert AA-modules {M,<.,.>1}\{ {\cal M}, < .,. >_1 \} and {M,<.,.>2}\{ {\cal M}, < .,. >_2 \} are shown to be *-isomorphic if and only if there exists a bounded AA-linear isomorphism SS of these two Hilbert AA-modules satisfying the identity <.,.>2<S(.),S(.)>1< .,. >_2 \equiv < S(.),S(.) >_1. This result extends other equivalent descriptions due to L.~G.~Brown, H.~Lin and E.~C.~Lance. An example of two non-isomorphic Hilbert C*-modules with *-isomorphic C*-algebras of ''compact''/adjointable bounded module operators is indicated.

Keywords

Cite

@article{arxiv.funct-an/9505001,
  title  = {Isomorphisms of Hilbert C*-Modules and $*$-Isomorphisms of Related Operator C*-Algebras},
  author = {Michael Frank},
  journal= {arXiv preprint arXiv:funct-an/9505001},
  year   = {2025}
}

Comments

5 pages, LaTeX file