I want to define multiplication on $L^1(\mathbb{R})$, of course, convolution is an allowed multiplication which makes $(L^1(\mathbb{R}),*)$ is a Banach algebra, I want to know if there are other products that multiplication $\bullet$ that $(L^1(\mathbb{R}),\bullet)$ is a Banach algebra.
2026-03-28 12:13:40.1774700020
Define multiplication on $L^1(\mathbb{R})$
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