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arXiv · 1807.00079

Pushforwards of Measures on Real Varieties under Maps with Rational Singularities

Andrew Reiser
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Abstract

Let $X,Y$ be algebraic varieties defined over $\Bbb R$. Assume $Y$ is smooth and $X$ is Gorenstein. Suppose $\varphi:X\to Y$ is a flat $\Bbb R$-morphism such that all the fibers have rational singularities. We show that the pushforward of any smooth, compactly supported measure on $X$ has a continuous density with respect to any smooth measure with non-vanishing density on $Y$. This extends a result of Aizenbud and Avni from the $p$-adic case to the archimedean case.

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Andrew Reiser. 2018-06-29. Pushforwards of Measures on Real Varieties under Maps with Rational Singularities. https://arxiv.org/abs/1807.00079

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