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arXiv · 2301.00978

On values of isotropic quadratic forms

Manoj Choudhuri·Prashant J. Makadiya
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Abstract

Let $K$ be a locally compact non-discrete field of characteristic $p>2$ and $Q$ be a non-degenerate isotropic binary quadratic form with coefficients in $K$. We obtain asymptotic estimates for the number of solutions in the two-fold product of a discrete subring inside $K$, of the inequalities of the form $|Q(x,y)|<\delta$ for some $\delta>0$, where $| \cdot |$ is an ultrametric absolute value on $K$. The estimates are obtained in terms of continued fraction expansions of the coefficients of the quadratic form $Q$.

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Manoj Choudhuri, Prashant J. Makadiya. 2023-01-03. On values of isotropic quadratic forms. https://arxiv.org/abs/2301.00978

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