Existence of ground states for approximately inner two--parameter $C_0$--groups on $C^*$--algebras

Document Type: Research Paper

Authors

Department of Mathematics, Mashhad Branch, Islamic Azad University, Mashhad, Iran.

Abstract

In this paper, we generalize the definitions of approximately inner $C_0$-groups and their ground states to the two- parameter case and study necessary and sufficient conditions for a state to be ground state. Also we prove that any approximately inner two- parameter $C_0$--group must have at least one ground state. Finally some applications are given.

Keywords

Main Subjects


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Volume 42, Issue 2
March and April 2016
Pages 435-446
  • Receive Date: 13 December 2013
  • Revise Date: 08 February 2015
  • Accept Date: 10 February 2015