Journal of the Ramanujan Mathematical Society

Volume 29, Issue 1, March 2014 pp. 63–74.

Finite dimensional Cebysev subspaces of C*-algebras

Authors: M. N. N. Namboodiri, S. Pramod and A. K. Vijayarajan
Author institution: Kerala School of Mathematics, Kozhikode, Kerala 673 571, India

Summary: In this note, a proposition due to G. K. Pedersen that characterizes a two dimensional Cebysev subspace of a C*-algebra is generalized to arbitrary finite dimension by introducing the concept of non-commutative Haar condition. In~addition, the spectral condition in the two dimensional case is linked to boundary representations and Choquet boundary. Examples are provided to illustrate a comparison with classical results for function spaces.

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