Definition:Convolution of Measures

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Definition

Let $\mu$ and $\nu$ be measures on the Borel $\sigma$-algebra $\BB^n$ on $\R^n$.


The convolution of $\mu$ and $\nu$, denoted $\mu * \nu$, is the measure defined by:

$\ds \mu * \nu: \BB^n \to \overline \R, \map {\mu * \nu} B := \int \map {\chi_B} {x + y} \map {\rd \mu} x \map {\rd \nu} y$

where $\chi_B$ is the characteristic function of $B$.


Also known as

Some sources prefer the original German term Faltung (literally: folding) over convolution.


Also see


Sources