Product of operators and numerical range preserving maps

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Product of Operators and Numerical Range Preserving Maps

Let V be the C∗-algebra B(H) of bounded linear operators acting on the Hilbert space H, or the Jordan algebra S(H) of self-adjoint operators in B(H). For a fixed sequence (i1, . . . , im) with i1, . . . , im ∈ {1, . . . , k}, define a product of A1, . . . , Ak ∈ V by A1 ∗ · · · ∗ Ak = Ai1 . . . Aim . This includes the usual product A1 ∗ · · · ∗ Ak = A1 · · ·Ak and the Jordan triple product A ∗ ...

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ژورنال

عنوان ژورنال: Studia Mathematica

سال: 2006

ISSN: 0039-3223,1730-6337

DOI: 10.4064/sm174-2-4