Abazari, R., Niknam, A. (2016). Existence of ground states for approximately inner two--parameter $C_0$--groups on $C^*$--algebras. Bulletin of the Iranian Mathematical Society, 42(2), 435-446.

R. Abazari; A. Niknam. "Existence of ground states for approximately inner two--parameter $C_0$--groups on $C^*$--algebras". Bulletin of the Iranian Mathematical Society, 42, 2, 2016, 435-446.

Abazari, R., Niknam, A. (2016). 'Existence of ground states for approximately inner two--parameter $C_0$--groups on $C^*$--algebras', Bulletin of the Iranian Mathematical Society, 42(2), pp. 435-446.

Abazari, R., Niknam, A. Existence of ground states for approximately inner two--parameter $C_0$--groups on $C^*$--algebras. Bulletin of the Iranian Mathematical Society, 2016; 42(2): 435-446.

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

^{}Department of Mathematics, Mashhad Branch, Islamic Azad University, Mashhad, Iran.

Receive Date: 13 December 2013,
Revise Date: 08 February 2015,
Accept Date: 10 February 2015

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.

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