The Cohen-Macaulay property of invariant rings over ring of integers of a global field

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autore principale: Puthenpurakal, Tony J.
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866909106073239552
author Puthenpurakal, Tony J.
author_facet Puthenpurakal, Tony J.
contents Let $A$ be the ring of integers of global field $K$. Let $G \subseteq GL_2(A)$ be a finite group. Let $G$ act linearly on $R = A[X,Y]$ (fixing $A$). Let $R^G$ be the ring of invariants. In the equi-characteristic case we prove $R^G$ is Cohen-Macaulay. In mixed characteristic case we prove that if for all primes $p$ dividing $|G|$ the Sylow $p$-subgroup of $G$ has exponent $p$ then $R^G$ is Cohen-Macaulay. We prove a similar case if for all primes $p$ dividing $|G|$ the prime $p$ is un-ramified in $K$.
format Preprint
id arxiv_https___arxiv_org_abs_2402_08962
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle The Cohen-Macaulay property of invariant rings over ring of integers of a global field
Puthenpurakal, Tony J.
Commutative Algebra
Number Theory
Primary 13A50, Secondary 13H10
Let $A$ be the ring of integers of global field $K$. Let $G \subseteq GL_2(A)$ be a finite group. Let $G$ act linearly on $R = A[X,Y]$ (fixing $A$). Let $R^G$ be the ring of invariants. In the equi-characteristic case we prove $R^G$ is Cohen-Macaulay. In mixed characteristic case we prove that if for all primes $p$ dividing $|G|$ the Sylow $p$-subgroup of $G$ has exponent $p$ then $R^G$ is Cohen-Macaulay. We prove a similar case if for all primes $p$ dividing $|G|$ the prime $p$ is un-ramified in $K$.
title The Cohen-Macaulay property of invariant rings over ring of integers of a global field
topic Commutative Algebra
Number Theory
Primary 13A50, Secondary 13H10
url https://arxiv.org/abs/2402.08962