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arXiv · 2509.16641

Inverse-closedness of weighted Schur and BGS type quasi-Banach algebras

Prakash A. Dabhi·Karishman B. Solanki
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Abstract

We prove that the weighted quasi-Banach algebras of operator valued matrices satisfying Schur and Baskakov-Gohberg-Sj\"ostrand (BGS) conditions are inverse-closed in the Banach algebra $B(\ell^2(X,\mathcal{H}))$ whenever the weight is admissible, where $\mathcal{H}$ is a Hilbert space and $X$ is a relatively separated subset of $\mathbb{R}^d$. Furthermore, we identify the Gel'fand space of weighted infinite variable group algebra $\ell^p_\omega(\mathbb{Z^N})$ for $0<p\leq1$, and establish inverse-closedness of infinite variable analogue of BGS-type algebra in $B(\ell^2(\mathbb{Z^N},\mathcal{H}))$.

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Prakash A. Dabhi, Karishman B. Solanki. 2025-09-20. Inverse-closedness of weighted Schur and BGS type quasi-Banach algebras. https://arxiv.org/abs/2509.16641

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