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arXiv · 2605.30549

On the density of rational lines on diagonal cubic hypersurfaces, II

Scott Parsell·Kiseok Yeon
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Abstract

In this paper, we establish the expected asymptotic formula for the number of rational lines on a diagonal cubic hypersurface in 18 or more variables, improving on recent work of the second author. This is achieved via a refined mean value estimate for minor arcs that non-trivially exploits a shifting variables argument in both underlying dimensions.

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Scott Parsell, Kiseok Yeon. 2026-05-28. On the density of rational lines on diagonal cubic hypersurfaces, II. https://arxiv.org/abs/2605.30549

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