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arXiv · 1907.02049

The inverse sieve problem for algebraic varieties over global fields

Juan Manuel Menconi·Marcelo Paredes·Román Sasyk
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Abstract

Let $K$ be a global field and let $Z$ be a geometrically irreducible algebraic variety defined over $K$. We show that if a big set $S\subseteq Z$ of rational points of bounded height occupies few residue classes modulo $\mathfrak{p}$ for many prime ideals $\mathfrak{p}$, then a positive proportion of $S$ must lie in the zero set of a polynomial of low degree that does not vanish at $Z$. This generalizes the main result of Walsh in [Duke Math. J., vol.161, (2012), 2001-2022].

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Juan Manuel Menconi, Marcelo Paredes, Román Sasyk. 2019-07-03. The inverse sieve problem for algebraic varieties over global fields. https://doi.org/10.4171/rmi%2F1261

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