activity
20182026
collaborators

7 papers

math.RT2026

Nilpotent quiver varieties with multiplicities and symmetrisable crystals

Victoria Hoskins, Joshua Jackson, Tanguy Vernet

We construct analogues of Nakajima's nilpotent quiver varieties for quivers with multiplicities, by developing new stability conditions for framed nilpotent quiver representations…

math.AG2025

Moduli spaces of representations of quivers with multiplicities via non-reductive GIT

Victoria Hoskins, Joshua Jackson, Tanguy Vernet

We construct new moduli spaces of quiver representations with multiplicities, i.e. over rings of truncated power series. This includes moduli of framed representations and analogue…

math.AG2025

The worst destabilizing 1-parameter subgroup for toric rational curves with one unibranch singularity

Joshua Jackson, David Swinarski

Kempf proved that when a point is unstable in the sense of Geometric Invariant Theory, there is a ``worst'' destabilizing 1-parameter subgroup . It is natural to ask: what a…

math.AG2024

Affine Non-Reductive GIT and moduli of representations of quivers with multiplicities

Eloise Hamilton, Victoria Hoskins, Joshua Jackson

We give an explicit approach to quotienting affine varieties by linear actions of linear algebraic groups with graded unipotent radical, using results from projective Non-Reductive…

math.AG2021

Quotients by Parabolic Groups and Moduli Spaces of Unstable Objects

Victoria Hoskins, Joshua Jackson

Motivated by constructing moduli spaces of unstable objects, we use new ideas in non-reductive GIT to construct quotients by parabolic group actions. For moduli problems with semis…

math.AG2021

Moduli Spaces of Unstable Objects: Sheaves of Harder-Narasimhan Length 2

Joshua Jackson

Given a moduli problem posed using Geometric Invariant Theory, one can use Non-Reductive Geometric Invariant Theory to quotient unstable HKKN strata and construct 'moduli spaces of…

math.AG2018

Variation of Non-reductive Geometric Invariant Theory

Gergely Bérczi, Joshua Jackson, Frances Kirwan

The wall-and-chamber structure of the dependence of the reductive GIT quotient on the choice of linearisation is well known. In this article, we first give a brief survey of recent…