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arXiv · 2606.06675

Multipliers of Beurling-Fourier algebras

Mahmood Alaghmandan·Olof Giselsson·Ebrahim Samei·Lyudmila Turowska
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Abstract

For a locally compact group G we introduce and study the reduced Beurling-Fourier-Stieltjes algebra, a weighted analogue of the reduced Fourier-Stieltjes algebra, together with the algebra of completely bounded multipliers of the associated weighted Fourier algebra. We show, in particular, that these two algebras coincide when G is amenable. For a general locally compact group G, we identify them as subspaces of the reduced Fourier-Stieltjes algebra and of the space of functions that locally belong to the Fourier algebra, respectively. Furthermore, we establish sufficient conditions on the group and the weight under which the algebra of completely bounded multipliers of the weighted Fourier algebra embeds into its unweighted counterpart.

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Mahmood Alaghmandan, Olof Giselsson, Ebrahim Samei, Lyudmila Turowska. 2026-06-04. Multipliers of Beurling-Fourier algebras. https://arxiv.org/abs/2606.06675

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