Browsing University of Waterloo by Author "Yahaghi, B.R."
Now showing items 1-3 of 3
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On *-similarity in C*-algebras
Marcoux, Laurent; Radjavi, Heydar; Yahaghi, B.R. (Instytut Matematyczny, 2020)Two subsets X and Y of a unital C -algebra A are said to be -similar via s 2 A1 if Y = s1Xs and Y = s1X s. We show that this relation imposes a certain structure on the sets X and Y, and that under certain natural ... -
Ranges of vector states on irreducible operator semigroups
Marcoux, L.W.; Omladič, M.; Popov, A.I.; Radjavi, H.; Yahaghi, B. (Springer, 2016)Let 𝜑 be a linear functional of rank one acting on an irreducible semigroup S of operators on a finite- or infinite-dimensional Hilbert space. It is a well-known and simple fact that the range of 𝜑 cannot be a singleton. ... -
Reducibility of operator semigroups and values of vector states
Marcoux, L.W.; Radjavi, H.; Yahaghi, B.R. (Springer, 2017-08-01)Let S be a multiplicative semigroup of bounded linear operators on a complex Hilbert space H, and let Ω be the range of a vector state on S so that Ω = {⟨Sξ, ξ⟩ : S ∈ S} for some fixed unit vector ξ ∈ H. We study the ...