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Spherical isometries of finite dimensional \(C^{\ast}\)-algebras. (English) Zbl 1371.46008

Summary: In this paper, it is shown that every surjective isometry between the unit spheres of two finite dimensional \(C^\ast\)-algebras extends to a real-linear Jordan isomorphism followed by multiplication operator by a fixed unitary element. This gives an affirmative answer to D. Tingley’s problem [Geom. Dedicata 22, 371–378 (1987; Zbl 0615.51005)] between two finite-dimensional \(C^\ast\)-algebras. Moreover, we show that if two finite dimensional \(C^\ast\)-algebras have isometric unit spheres, then they are isomorphic.

MSC:

46B04 Isometric theory of Banach spaces
46B25 Classical Banach spaces in the general theory
46L05 General theory of \(C^*\)-algebras

Citations:

Zbl 0615.51005
Full Text: DOI

References:

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