Abstract
Given a Banach algebra A, with an amenable ideal I and amenable quotient A/I, we seek for relations among the amenability constants of A, A/I and I. We also provide some examples as applications. In particular, we propose a suitable approach to the amenability constant of A #. Finally, we give an upper bound for the amenability constant of the augmentation ideal L 10 (G) of an amenable σ-compact group G.
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Original Russian Text Copyright © 2014 Soroushmehr M.
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Translated from Sibirskiĭ Matematicheskiĭ Zhurnal, Vol. 55, No. 6, pp. 1391–1395, November–December, 2014.
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Soroushmehr, M. A note on the amenability constant of Banach algebras. Sib Math J 55, 1133–1136 (2014). https://doi.org/10.1134/S0037446614060160
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DOI: https://doi.org/10.1134/S0037446614060160