English

Orthogonally additive holomorphic maps between C*-algebras

Operator Algebras 2015-12-25 v1 Functional Analysis

Abstract

Let A,BA,B be C*-algebras, BA(0;r)B_A(0;r) the open ball in AA centered at 00 with radius r>0r>0, and H:BA(0;r)BH:B_A(0;r)\to B an orthogonally additive holomorphic map. If HH is zero product preserving on positive elements in BA(0;r)B_A(0;r), we show, in the commutative case when A=C0(X)A=C_0(X) and B=C0(Y)B=C_0(Y), that there exist weight functions hnh_n's and a symbol map φ:YX\varphi: Y\to X such that H(f)=n1hn(fφ)n,fBC0(X)(0;r). H(f)=\sum_{n\geq1} h_n (f\circ\varphi)^n, \quad\forall f\in B_{C_0(X)}(0;r). In the general case, we show that if HH is also conformal then there exist central multipliers hnh_n's of BB and a surjective Jordan isomorphism J:ABJ: A\to B such that H(a)=n1hnJ(a)n,aBA(0;r). H(a) = \sum_{n\geq1} h_n J(a)^n, \quad\forall a\in B_A(0;r). If, in addition, HH is zero product preserving on the whole BA(0;r)B_A(0;r), then JJ is an algebra isomorphism. %Similar conclusions hold for orthogonally additive nn-homogeneous polynomials which are nn-isometries.

Keywords

Cite

@article{arxiv.1512.07714,
  title  = {Orthogonally additive holomorphic maps between C*-algebras},
  author = {Qingying Bu and Ming-Hsiu Hsu and Ngai-Ching Wong},
  journal= {arXiv preprint arXiv:1512.07714},
  year   = {2015}
}

Comments

23 pages, 1st draft 2013.8.9, this version 2015.3.20

R2 v1 2026-06-22T12:17:19.559Z