arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1902.06372math.AG
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雅可比曲面的同源分量

Isogenous components of Jacobian surfaces

Lubjana Beshaj, Artur Elezi, Tony Shaska

AI总结:

该研究针对亏格2曲线的雅可比簇,在不同自同构群、可约性参数及同源次数下,计数并分析椭圆分量的同源性,确定相关曲面,指出正特征下的结果可应用于密码学。

摘要:

设$\u214b$是定义在域$K$上的亏格2曲线,$\text{char}\\, K = p \geq 0$,$\text{Jac}(\u214b, \iota)$是其雅可比簇,其中$\text{Jac}(\u214b)$的主极化$\text{Jac}(\u214b)$与$\u214b$相关联。假设$\text{Jac}(\u214b)$在几何上是$(n,n)$-可约的,且$E_1$和$E_2$是其椭圆分量。当$K$为数域时,我们在那些允许在$K$上有模型的曲线中,按几何同构对这类曲线进行计数。对于$n=2$且$\text{Aut}(\u214b) \cong V_4$,我们证明,对每个$N=2,3,5,7$,存在无穷多条曲线$\u214b$使得$E_1$和$E_2$是$N$-同源的。对于$n=2$且$\text{Aut}(\u214b) \cong D_4$,来自两类非超椭圆对合的椭圆商总是2-同源的,且对每个$N=3,5,7$,只有有限多条曲线使得它们是$N$-同源的。对于$n=3$,对每个$N=2,3,5$,存在无穷多条曲线具有$N$-同源的椭圆分量,而对于$N=7$,只有有限多条这样的曲线在$\u211a$上有模型。此外,我们确定了上述$\text{Jac}(\u214b)$的库默尔曲面和志田-猪濑曲面,并表明正特征$p>2$下的此类结果如何在密码学中具有良好应用。

英文摘要:

Let $\mathcal{X}$ be a genus 2 curve defined over a field $K$, $\mathrm{char}\, K = p \geq 0$, and $\mathrm{Jac}(\mathcal{X}, ι)$ its Jacobian, where $ι$ is the principal polarization of $\mathrm{Jac}(\mathcal{X})$ attached to $\mathcal{X}$. Assume that $\mathrm{Jac}(\mathcal{X})$ is geometrically $(n,n)$-reducible with $E_1$ and $E_2$ its elliptic components. When $K$ is a number field, we count such curves up to geometric isomorphism, among those admitting a model over $K$. For $n=2$ and $\mathrm{Aut}(\mathcal{X}) \cong V_4$ we prove that, for each $N=2,3,5,7$, there are infinitely many curves $\mathcal{X}$ for which $E_1$ and $E_2$ are $N$-isogenous. For $n=2$ and $\mathrm{Aut}(\mathcal{X}) \cong D_4$ the elliptic quotients from the two classes of nonhyperelliptic involutions are always $2$-isogenous, and for each $N=3,5,7$ only finitely many curves have them $N$-isogenous. For $n=3$ there are infinitely many curves with $N$-isogenous elliptic components for each $N=2,3,5$, while for $N=7$ there are only finitely many such curves with a model over $\mathbb{Q}$. Furthermore, we determine the Kummer and the Shioda-Inose surfaces for the above $\mathrm{Jac}(\mathcal{X})$ and show how such results in positive characteristic $p>2$ suggest nice applications in cryptography.

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。

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