activity
20122025
most citedFI-modules over Noetherian rings

181 citations · 368 across the 15 of their papers we have counts for

collaborators

19 papers

math.AT2025

Corrigendum to "Stability in the high-dimensional cohomology of congruence subgroups" [Compos. Math. 156 (2020), no. 4, 822-861]

Jeremy Miller, Rohit Nagpal, Peter Patzt

After the publication of [Compos. Math. 156 (2020), no. 4, 822-861], Andrew Putman pointed out a mistake in our paper and helped us fix it. In this note, we will explain what this…

math.AC2025

Symmetric modules over the infinite polynomial ring I: nilpotent quotients

Rohit Nagpal, Andrew Snowden, Teresa Yu

Cohen proved that the infinite variable polynomial ring is noetherian with respect to the action of the infinite symmetric group . The first two…

math.AC2021★ 4 cited

Symmetric ideals of the infinite polynomial ring

Rohit Nagpal, Andrew Snowden

Let be the infinite variable polynomial ring, equipped with the natural action of the infinite symmetric group . We classify the $\math…

math.RT2021★ 6 cited

On the geometry and representation theory of isomeric matrices

Rohit Nagpal, Steven V Sam, Andrew Snowden

The space of complex matrices can be regarded as an algebraic variety on which the group acts. There is a rich interaction between geome…

math.AG2020★ 7 cited

Symmetric subvarieties of infinite affine space

Rohit Nagpal, Andrew Snowden

We classify the subvarieties of infinite dimensional affine space that are stable under the infinite symmetric group. We determine the defining equations and point sets of these va…

math.RT2019

Periodicity in the cohomology of finite general linear groups via q-divided powers

Rohit Nagpal, Steven V Sam, Andrew Snowden

We show that canonically admits the structure of a module over the -divided power algebra (assuming …

math.RT2019★ 1 cited

The semi-linear representation theory of the infinite symmetric group

Rohit Nagpal, Andrew Snowden

We study the category of smooth semilinear representations of the infinite symmetric group over the field of rational functions in infinitely many variables. We estab…

math.RT2018

VI modules in non-describing characteristic, Part II

Rohit Nagpal

We classify all irreducible generic -modules in non-describing characteristic. Our result degenerates to yield a classification of irreducible generic -mo…

math.AT2018★ 12 cited

Stability in the high-dimensional cohomology of congruence subgroups

Jeremy Miller, Rohit Nagpal, Peter Patzt

We prove a representation stability result for the codimension-one cohomology of the level three congruence subgroup of . This is a special case of a que…

math.RT2017★ 12 cited

modules in non-describing characteristic, Part I

Rohit Nagpal

Let be the category of finite dimensional -vector spaces whose morphisms are injective linear maps, and let be a noetherian ring. We study…

math.RT2017

Linear and quadratic ranges in representation stability

Thomas Church, Jeremy Miller, Rohit Nagpal +1

We prove two general results concerning spectral sequences of -modules. These results can be used to significantly improve stable ranges in a large portion of the stab…

math.RT2017★ 17 cited

Periodicity in the cohomology of symmetric groups via divided powers

Rohit Nagpal, Andrew Snowden

A famous theorem of Nakaoka asserts that the cohomology of the symmetric group stabilizes. The first author generalized this theorem to non-trivial coefficient systems, in the form…

math.AC2017★ 17 cited

Regularity of FI-modules and local cohomology

Rohit Nagpal, Steven V Sam, Andrew Snowden

We resolve a conjecture of Li and Ramos that relates the regularity of an FI-module to its local cohomology groups. This is an analogue of the familiar relationship between regular…

math.RT2016★ 24 cited

Noetherianity of some degree two twisted skew-commutative algebras

Rohit Nagpal, Steven V Sam, Andrew Snowden

A major open problem in the theory of twisted commutative algebras (tca's) is proving noetherianity of finitely generated tca's. For bounded tca's this is easy, in the unbounded ca…

math.AC2016

Gröbner coherent rings and modules

Rohit Nagpal, Andrew Snowden

Let be a graded ring. We introduce a class of graded -modules called Gröbner-coherent modules. Roughly, these are graded -modules that are coherent as ungraded modules be…

math.AC2016

The module theory of divided power algebras

Rohit Nagpal, Andrew Snowden

We study modules for the divided power algebra in a single variable over a commutative noetherian ring . Our first result states that is a coherent ring. In fact, we sho…

math.RT2015★ 50 cited

FI-modules and the cohomology of modular representations of symmetric groups

Rohit Nagpal

An FI-module over a commutative ring encodes a sequence of representations of the symmetric groups over . In t…

math.AC2015★ 37 cited

Noetherianity of some degree two twisted commutative algebras

Rohit Nagpal, Steven V Sam, Andrew Snowden

In recent years, researchers have discovered various large algebraic structures that have surprising finiteness properties, such as FI-modules and Delta-modules. In this paper, we…

math.RT2012★ 181 cited

FI-modules over Noetherian rings

Thomas Church, Jordan S. Ellenberg, Benson Farb +1

FI-modules were introduced by the first three authors in [CEF] to encode sequences of representations of symmetric groups. Over a field of characteristic 0, finite generation of an…