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arXiv · 1411.4728

Genus Periods, Genus Points and Congruent Number Problem

Ye Tian·Xinyi Yuan·Shouwu Zhang
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Abstract

In this paper, based on an ideal of Tian, we establish a new sufficient condition for a positive integer to be a congruent number in terms of Legendre symbols of prime factors of the positive integer. Our criterion generalizes previous criterions of Heegner, and Birch--Stephens, Monsky, and Tian, and conjecturally provides a list of positive density of congruent numbers. Our method of proving our criterion is to give formulae for the analytic Tate--Shafarevich number in terms of the so-called genus periods and genus points. These formulae are derived from the Waldspurger formula and the generalized Gross--Zagier formula of Yuan-Zhang-Zhang.

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Ye Tian, Xinyi Yuan, Shouwu Zhang. 2014-11-18. Genus Periods, Genus Points and Congruent Number Problem. https://arxiv.org/abs/1411.4728

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