Abstract
Let A and B be uniformly closed function algebras on locally compact Hausdorff spaces with Choquet boundaries Ch A and ChB, respectively. We prove that if T: A → B is a surjective real-linear isometry, then there exist a continuous function κ: ChB → {z ∈ ℂ: |z| = 1}, a (possibly empty) closed and open subset K of ChB and a homeomorphism φ: ChB → ChA such that T(f) = κ(f ∘φ) on K and \(T\left( f \right) = \kappa \overline {fo\phi }\) on ChB \ K for all f ∈ A. Such a representation holds for surjective real-linear isometries between (not necessarily uniformly closed) function algebras.
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Miura, T. Real-linear isometries between function algebras. centr.eur.j.math. 9, 778–788 (2011). https://doi.org/10.2478/s11533-011-0044-9
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DOI: https://doi.org/10.2478/s11533-011-0044-9