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arXiv · 1610.07260

Beyond Expansion III: Reciprocal Geodesics

Jean Bourgain·Alex Kontorovich
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Abstract

We prove the existence of infinitely many low-lying and fundamental closed geodesics on the modular surface which are reciprocal, that is, invariant under time reversal. The method combines ideas from Parts I and II of this series, namely the dispersion method in bilinear forms, as applied to thin semigroups coming from restricted continued fractions.

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Jean Bourgain, Alex Kontorovich. 2016-10-24. Beyond Expansion III: Reciprocal Geodesics. https://doi.org/10.1215/00127094-2019-0056

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