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arXiv · 2006.08113

Constructing congruent number elliptic curves using 2-descent

Raiza Corpuz
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Abstract

A positive integer that is the area of some rational right triangle is called a congruent number. In an algebraic point of view, being a congruent number means satisfying a system of equations. As early as the 1800s, it is understood that if $n$ is a congruent number, then the equation $nm^2 = uv(u^2 - v^2)$ has a solution in $\mathbb{Z}$. Using the relation between congruent numbers and elliptic curves $E_n: y^2 = x^3 - n^2 x$ which was established in the 1900s, we will prove that the converse of this two century-old result holds as well. In addition to this, we present another proof of the converse using the method of 2-descent. Towards the end of this paper, we demonstrate how one can use our proof to construct subfamilies of $E_n$ with rank at least 2 and 3.

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Raiza Corpuz. 2020-06-15. Constructing congruent number elliptic curves using 2-descent. https://arxiv.org/abs/2006.08113

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