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arXiv · 2003.13829

Critical loci of convex domains in the plane

Dmitry Kleinbock·Anurag Rao·Srinivasan Sathiamurthy
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Abstract

Let $K$ be a bounded convex domain in $\mathbb{R}^2$ symmetric about the origin. The critical locus of $K$ is defined to be the (non-empty compact) set of lattices $\Lambda$ in $\mathbb{R}^2$ of smallest possible covolume such that $\Lambda \cap K= \lbrace 0\rbrace$. These are classical objects in geometry of numbers; yet all previously known examples of critical loci were either finite sets or finite unions of closed curves. In this paper we give a new construction which, in particular, furnishes examples of domains having critical locus of arbitrary Hausdorff dimension between $0$ and $1$.

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Dmitry Kleinbock, Anurag Rao, Srinivasan Sathiamurthy. 2020-03-30. Critical loci of convex domains in the plane. https://arxiv.org/abs/2003.13829

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