$\mathbb{P}^{1}$上动力系统的定义域:Silverman结果的改进
数论
2024-05-13 v2 代数几何
动力系统
摘要
J. Silverman证明了上的动力系统如果是多项式或具有偶数次数,则下降到模域,但对于奇数次的非多项式系统,情况尚不明确。我们给出了上哪些动力系统下降到模域的完整刻画。
关键词
引用
@article{arxiv.2405.03612,
title = {Fields of definition of dynamical systems on $\mathbb{P}^{1}$. Improvements on a result of Silverman},
author = {Giulio Bresciani},
journal= {arXiv preprint arXiv:2405.03612},
year = {2024}
}
备注
There is a mistake in the proof of the main theorem. In the middle of page 5, we state that \phi has equal orders of vanishing in 0 and \infty. However, the argument only proves the weaker statement that the ramification degrees are equal. This is not sufficient to conclude