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Related papers: Invariants for non-reductive group actions

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Given an algebraic torus action on a normal projective variety with finitely generated total coordinate ring, we study the GIT-equivalence for not necessarily ample linearized divisors, and we provide a combinatorial description of the…

Algebraic Geometry · Mathematics 2007-05-23 Florian Berchtold , Juergen Hausen

We consider an arbitrary representation of the additive group over a field of characteristic zero and give an explicit description of a finite separating set in the corresponding ring of invariants.

Commutative Algebra · Mathematics 2013-02-05 Emilie Dufresne , Jonathan Elmer , Müfit Sezer

We survey recent results on multiple transitivity of automorphism groups of affine algebraic varieties. We consider the property of infinite transitivity of the special automorphism group, which is equivalent to flexibility of the…

Algebraic Geometry · Mathematics 2023-04-04 Ivan Arzhantsev

The study of $G$-equivariant operators is of great interest to explain and understand the architecture of neural networks. In this paper we show that each linear $G$-equivariant operator can be produced by a suitable permutant measure,…

Group Theory · Mathematics 2022-03-11 Giovanni Bocchi , Stefano Botteghi , Martina Brasini , Patrizio Frosini , Nicola Quercioli

We study linear actions of finite groups in small dimensions, up to equivariant birationality.

Algebraic Geometry · Mathematics 2023-02-07 Yuri Tschinkel , Kaiqi Yang , Zhijia Zhang

We generalize the theory of the second invariant cohomology group $H^2_{\rm inv}(G)$ for finite groups $G$, developed in [Da2,Da3,GK], to the case of affine algebraic groups $G$, using the methods of [EG1,EG2,G]. In particular, we show that…

Quantum Algebra · Mathematics 2017-10-12 Pavel Etingof , Shlomo Gelaki

We construct a projective variety with discrete, non-finitely generated automorphism group. As an application, we show that there exists a complex projective variety with infinitely many non-isomorphic real forms.

Algebraic Geometry · Mathematics 2017-02-08 John Lesieutre

We consider actions of reductive groups on a varieties with finitely generated Cox ring, e.g., the classical case of a diagonal action on a product of projective spaces. Given such an action, we construct via combinatorial data in the Cox…

Algebraic Geometry · Mathematics 2008-12-19 Ivan V. Arzhantsev , Juergen Hausen

This paper extends classical results in the invariant theory of finite groups and finite group schemes to the actions of finite Hopf algebras on commutative rings.

Rings and Algebras · Mathematics 2007-05-23 S. Skryabin

We study Artin-Schelter Gorenstein fixed subrings of some Artin-Schelter regular algebras of dimension 2 and 3 under finite group actions, and prove a noncommutative version of the Kac-Watanabe and Gordeev theorem for these algebras.

Rings and Algebras · Mathematics 2013-08-05 E. Kirkman , J. Kuzmanovich , J. J. Zhang

We study degree bounds on rational but not necessarily polynomial generators for the field $\mathbf{k}(V)^G$ of rational invariants of a linear action of a finite abelian group. We show that lattice-theoretic methods used recently by the…

Commutative Algebra · Mathematics 2024-06-18 Ben Blum-Smith

The existence of invariant generators for distributions satisfying a compatibility condition with the symmetry algebra is proved.

Differential Geometry · Mathematics 2011-10-17 Madeleine Jotz , Tudor S. Ratiu

For a connected reductive group G and a finite-dimensional G-module V, we study the invariant Hilbert scheme that parameterizes closed G-stable subschemes of V affording a fixed, multiplicity-finite representation of G in their coordinate…

Algebraic Geometry · Mathematics 2007-05-23 Valery Alexeev , Michel Brion

Given a group action, known by its infinitesimal generators, we exhibit a complete set of syzygies on a generating set of differential invariants. For that we elaborate on the reinterpretation of Cartan's moving frame by Fels and Olver…

Symbolic Computation · Computer Science 2008-11-03 Evelyne Hubert

We present a Geometric Invariant Theory (GIT) construction which allows us to construct good projective degenerations of Hilbert schemes of points for simple degenerations. A comparison with the construction of Li and Wu shows that our GIT…

Algebraic Geometry · Mathematics 2017-10-25 Martin G. Gulbrandsen , Lars H. Halle , Klaus Hulek

We consider the problem of classifying linear systems of hypersurfaces (of a fixed degree) in some projective space up to projective equivalence via geometric invariant theory (GIT). We provide an explicit criterion that solves the problem…

Algebraic Geometry · Mathematics 2022-12-29 Masafumi Hattori , Aline Zanardini

Let $\mathcal{G}$ be an algebraic quantum group and $\mathcal{U}$ a compact quantum subgroup. Given a left $\hat{\mathcal{U}}$-module algebra A with unit, we can endow $A\otimes\mathcal{G}$ with a structure of a right…

Quantum Algebra · Mathematics 2024-11-27 Eugenia Ellis , Ana González , Gisela Tartaglia

Given a certain kind of linear representation of a reductive group, referred to as a quasi-symmetric representation in recent work of \v{S}penko and Van den Bergh, we construct equivalences between the derived categories of coherent sheaves…

Algebraic Geometry · Mathematics 2021-08-02 Daniel Halpern-Leistner , Steven V Sam

This paper is dedicated to the problem of infinite transitivity for algebraically generated automorphism groups of the affine plane. We provide a necessary and sufficient condition of infinite transitivity for a large family of subgroups…

Algebraic Geometry · Mathematics 2022-02-07 Alisa Chistopolskaya , Gregory Taroyan

We describe the GIT-equivalence classes of linearized ample line bundles for the diagonal actions of the linear algebraic groups $SL(V)$ and $SO(V)$ on ${\mathbb{P}(V)^{m_1}\times \mathbb{P}(V^*)^{m_2}}$ and $\mathbb{P}(V)^m$ respectively.

Algebraic Geometry · Mathematics 2012-03-19 Polina Yu. Kotenkova