New criteria for positive-definite distributions
Julián Haddad
Volume 69, no. 2
(2026),
pp. 475–484
Published online (final version): July 24, 2026
https://doi.org/10.33044/revuma.5697
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Abstract
We establish several sufficient conditions under which a locally-integrable function
$f:\mathbb{R}^n \to \mathbb{R}$ represents a positive-definite distribution. In
particular, we consider functions of the form $f(\|x\|)$, where $\|\cdot\|$ is a fixed
norm in $\mathbb{R}^n$.
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