Why we have “$\Delta \Gamma = \delta$”, in $\mathbb{R}^{n}$, where $\Gamma$ is fundamental solution and $\delta$ is the dirac measure?

Why we have "$\Delta \Gamma = \delta$", in $\mathbb{R}^{n}$, where $\Gamma$ is fundamental solution and $\delta$ is the dirac measure?

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 Did you read at least the wiki article on fundamental solutions? en.wikipedia.org/wiki/Fundamental_solution – Vobo Jul 17 '12 at 17:08 I turned the primes $''$ into quotation marks. Hope it was appropriate... – Dirk Jul 17 '12 at 17:18 I think the answer is "because we/they defined fundamental solution in this way". – user31373 Jul 18 '12 at 0:32