arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1111.3654math.NT
收藏

普通变形环的奇异性

Singularities of ordinary deformation rings

Andrew Snowden

摘要:

设R^univ是局部伽罗瓦群的剩余表示的泛变形环. Kisin证明了MaxSpec(R^univ[1/p])中的许多位点都是Zebrski闭的,并给出了研究R^univ中相应商的通有纤维的方法.然而,他的方法给出的关于p反演前的商环的信息很少.精确地说,假设V_0是平凡的二维表示,设R是R^univ的唯一Z_p-平坦和约化商,使得MaxSpec(R[1/p])由Hodge-Tate权为0和1的常表示组成。我们描述的函子的点(略有修改的版本)R,并表明,不可约组件的规范(R)是正常的,科恩-麦考利,而不是Gorenstein。这在整体变形环上有两个众所周知的应用:第一,使用这些局部条件的整体变形环是无挠的;第二,基辛的R[1/p]=T[1/p]定理可以在这种情况下升级为R=T定理。

英文摘要:

Let R^univ be the universal deformation ring of a residual representation of a local Galois group. Kisin showed that many loci in MaxSpec(R^univ[1/p]) of interest are Zariski closed, and gave a way to study the generic fiber of the corresponding quotient of R^univ. However, his method gives little information about the quotient ring before inverting p. We give a method for studying this quotient in certain cases, and carry it out in the simplest non-trivial case. Precisely, suppose that V_0 is the trivial two dimensional representation and let R be the unique Z_p-flat and reduced quotient of R^univ such that MaxSpec(R[1/p]) consists of ordinary representations with Hodge--Tate weights 0 and 1. We describe the functor of points of (a slightly modified version of) R and show that the irreducile components of Spec(R) are normal, Cohen--Macaulay and not Gorenstein. This has two well-known applications to global deformation rings: first, a global deformation ring employing these local conditions is torsion-free; and second, Kisin's R[1/p]=T[1/p] theorem can be upgraded in this setting to an R=T theorem.

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。

↑