发表机构
Indian Institute of Technology Madras; Indian Statistical Institute; Sabancı Üniversitesi(印度理工学院马德拉斯分校; 印度统计研究所; 萨班哲大学)
机构由 AI 辅助整理,请以论文原文为准。AI 中文总结
本文研究赋值域上多项式复合的单生成性,通过判别式显式公式和临界值平方自由条件给出判据,并推广至迭代情形,构造了新的无限单生成域族。
AI 中文摘要
确定一个代数数域是否具有幂积分基是一个经典问题,但对于由多项式复合和动力学迭代定义的域来说可能很困难。在本文中,我们研究了复合 $f(h(x))$ 的单生成性,其中 $f(x)$ 和 $h(x)$ 是任意 Krull 赋值环上的首一多项式,且 $h(x)$ 是三项式。我们推导了复合的判别式的显式公式,并利用它们刻画了 $f(h(x))$ 何时生成单生成域。特别地,我们将复合的单生成性与 $f(x)$ 的单生成性以及 $h(x)$ 的临界值的显式平方自由条件联系起来。我们进一步将结果扩展到多项式迭代,并获得了二项式迭代的单生成性判据,产生了新的无限单生成域族。最后,我们给出了定量结果,并用几个例子说明了我们的判据。
英文摘要
Determining whether an algebraic number field admits a power integral basis is a classical problem, but it can be difficult for fields defined by polynomial compositions and dynamical iterates. In this paper, we study the monogeneity of compositions $f(h(x))$, where $f(x)$ and $h(x)$ are monic polynomials over an arbitrary Krull valuation ring and $h(x)$ is a trinomial. We derive explicit formulas for the discriminant of the composition and use them to characterize when $f(h(x))$ generates a monogenic field. In particular, we relate the monogeneity of the composition to that of $f(x)$ and to explicit square-free conditions on the critical values of $h(x)$. We further extend the results to polynomial iteration and obtain a criterion for the monogeneity of binomial iterates, yielding new infinite families of monogenic fields. Finally, we give quantitative results and illustrate our criteria with several examples.
Comments27 pages