English

Commutativity preserving mappings in Banach algebras

Rings and Algebras 2026-05-11 v1 Functional Analysis

Abstract

Let AA and BB be unital complex Banach algebras having no quotients isomorphic to C\mathbb{C} or M2(C)M_2(\mathbb{C}). Assume additionally that BB is semisimple. If a surjective additive mapping Φ ⁣:AB\Phi\colon A\to B satisfies [Φ(x2),Φ(x)]=0[\Phi(x^2),\Phi(x)] = 0 for all xAx\in A, then there exist a surjective direct sum of an additive homomorphism and an additive anti-homomorphism Ψ ⁣:AB\Psi\colon A\to B, an invertible element λZ(B)\lambda\in\mathcal{Z}(B), and an additive mapping ζ ⁣:AZ(B)\zeta\colon A\to\mathcal{Z}(B) such that Φ(x)=λΨ(x)+ζ(x)\Phi(x)=\lambda\Psi(x)+\zeta(x) for all xAx\in A.

Keywords

Cite

@article{arxiv.2605.07666,
  title  = {Commutativity preserving mappings in Banach algebras},
  author = {M. Brešar and G. M. Escolano and A. Peralta and A. R. Villena},
  journal= {arXiv preprint arXiv:2605.07666},
  year   = {2026}
}