^{1}Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Islamic Republic of Iran.

^{2}Faculty of Sciences, Sahand University of Technology, Tabriz, Islamic Republic of Iran.

Abstract

In this paper, we introduce a notion of property (T) for a C∗- dynamical system (A, G, α) consisting of a unital C∗-algebra A, a locally compact group G, and an action α on A. As a result, we show that if A has strong property (T) and G has Kazhdan’s property (T), then the triple (A, G, α) has property (T).

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