Abstract
The Gleason–Kahane–Żelazko theorem states that a linear functional on a Banach algebra that is non-zero on invertible elements is necessarily a scalar multiple of a character. Recently this theorem has been extended to certain Banach function spaces that are not algebras. In this article we present a brief survey of these extensions.
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Communicated by L. Molnár
Supported byan NSERC grant.
†Supported by grants from NSERCand the Canada Research Chairs program.
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Mashreghi, J., Ransford, T. Gleason–Kahane–Zelazko theorems in function spaces. ActaSci.Math. 84, 227–238 (2018). https://doi.org/10.14232/actasm-017-323-8
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DOI: https://doi.org/10.14232/actasm-017-323-8