English

Thompson-type formulae

Functional Analysis 2011-07-05 v1

Abstract

Let X and Y be two nxn Hermitian matrices. In the article "Proof of a conjectured exponential formula" (Linear and Multilinear Algebra (19) 1986, 187-197) R. C. Thompson proved that there exist two nxn unitary matrices U and V such that eiXeiY=ei(UXU+VBV). e^{i X}e^{i Y}=e^{i (UXU^*+VBV^*)}. In this note we consider extensions of this result to compact operators as well as to operators in an embeddable II1_1 factor.

Keywords

Cite

@article{arxiv.1107.0348,
  title  = {Thompson-type formulae},
  author = {Jorge Antezana and Gabriel Larotonda and Alejandro Varela},
  journal= {arXiv preprint arXiv:1107.0348},
  year   = {2011}
}
R2 v1 2026-06-21T18:30:53.470Z