arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1806.01751math.NTmath.AG
收藏

亏格为零的模曲线的模对应的相交数

Intersection numbers of modular correspondences for genus zero modular curves

Yuya Murakami

摘要:

本文在同余子群$Γ_0(M)$上引入模多项式,当$ X_0(M) $亏格为零时,该多项式由$ X_0(M) $的Hauptmodul定义.证明了由两个模多项式定义的两条曲线的相交数可以表示为$\mathbb{Z}$上正定二元二次型的$\mathrm{SL}_2(\mathbb{Z})$ -等价类的个数之和.我们还表明,相交数也可以组合写的Siegel Eisenstein系列的傅傅里叶系数的度为2,重量为2的$\mathrm{Sp}_2(\mathbb{Z})$。

英文摘要:

In this paper, we introduce modular polynomials for the congruence subgroup $Γ_0(M)$ when $ X_0(M) $ has genus zero and therefore the polynomials are defined by a Hauptmodul of $ X_0(M) $. We show that the intersection number of two curves defined by two modular polynomials can be expressed as the sum of the numbers of $\mathrm{SL}_2(\mathbb{Z})$-equivalence classes of positive definite binary quadratic forms over $\mathbb{Z}$. We also show that the intersection numbers can be also combinatorially written by Fourier coefficients of the Siegel Eisenstein series of degree 2, weight 2 with respect to $\mathrm{Sp}_2(\mathbb{Z})$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑