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arXiv · 2008.08962

The density of rational lines on hypersurfaces: A bihomogeneous perspective

Julia Brandes
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Abstract

Let $F$ be a non-singular homogeneous polynomial of degree $d$ in $n$ variables. We give an asymptotic formula of the pairs of integer points $(\mathbf x, \mathbf y)$ with $|\mathbf x| \le X$ and $|\mathbf y| \le Y$ which generate a line lying in the hypersurface defined by $F$, provided that $n > 2^{d-1}d^4(d+1)(d+2)$. In particular, by restricting to Zariski-open subsets we are able to avoid imposing any conditions on the relative sizes of $X$ and $Y$.

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Julia Brandes. 2020-08-20. The density of rational lines on hypersurfaces: A bihomogeneous perspective. https://arxiv.org/abs/2008.08962

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