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Related papers: The representation type of determinantal varieties

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The irreducible components of varieties parametrizing the finite dimensional representations of a finite dimensional algebra $\Lambda$ are explored, with regard to both their geometry and the structure of the modules they encode. Provided…

Representation Theory · Mathematics 2014-07-11 E. Babson , B. Huisgen-Zimmermann , R. Thomas

We show that all reduced closed subschemes of projective space that have a Cohen-Macaulay graded coordinate ring are of wild Cohen-Macaulay type, except for a few cases which we completely classify.

Algebraic Geometry · Mathematics 2024-09-04 Daniele Faenzi , Joan Pons-Llopis

We construct every finite-dimensional irreducible representation of the simple Lie algebra of type $\mathsf{E}_{7}$ whose highest weight is a nonnegative integer multiple of the dominant minuscule weight associated with the type…

Representation Theory · Mathematics 2023-03-14 Robert G. Donnelly , Molly W. Dunkum , Austin White

We find the irreducible decomposition of the Weil representation of the unitary group $\mathrm{U}_{2n}(A)$, where $A$ is a ramified quadratic extension of a finite, commutative, local, principal ideal ring $R$ and the nilpotency degree of…

Representation Theory · Mathematics 2018-05-08 Allen Herman , Momuita Shau , Fernando Szechtman

This manuscript has two goals: 1. To write an explicit description of the degenerate residual spectrum of the split, simple, simply-connected, exceptional groups of type $E_n$ (for $n=6,7,8$). 2. To set a practical guide for similar…

Representation Theory · Mathematics 2023-12-05 Hezi Halawi , Avner Segal

For a tuple of square matrices $A_1,...,A_n$ the determinantal hypersurface is defined as \begin{eqnarray*} &\sigma(A_1,...,A_n)= \\ &\Big\{[x_1:\cdots :x_n]\in \C{\mathbb P}^{n-1}: det(x_1A_1+\cdots +x_nA_n)=0\Big \}. \end{eqnarray*} In…

Spectral Theory · Mathematics 2022-03-15 Michael Stessin

To each irreducible infinite dimensional representation $(\pi,\cH)$ of a $C^*$-algebra $\cA$, we associate a collection of irreducible norm-continuous unitary representations $\pi_{\lambda}^\cA$ of its unitary group $\U(\cA)$, whose…

Representation Theory · Mathematics 2011-02-01 Daniel Beltita , Karl-Hermann Neeb

We consider normal projective n-dimensional varieties X whose anticanonical divisor class -K is ample and where every Weil divisor is a rational multiple of K. The index i is the largest integer such that K/i exists as a Weil divisor. We…

Algebraic Geometry · Mathematics 2016-09-07 Ziv Ran

We study a family of determinantal ideals whose decompositions encode the structural zeros in conditional independence models with hidden variables. We provide explicit decompositions of these ideals and, for certain subclasses of models,…

Commutative Algebra · Mathematics 2025-12-09 Yulia Alexandr , Kristen Dawson , Hannah Friedman , Fatemeh Mohammadi , Pardis Semnani , Teresa Yu

A torsion free sheaf on a hyperk\"ahler variety $X$ is modular if the discriminant satisfies a certain condition, for example if it is a multiple of $c_2(X)$ the sheaf is modular. The definition is taylor made for torsion-free sheaves on a…

Algebraic Geometry · Mathematics 2021-04-28 Kieran G. O'Grady

We give a graded dimension formula described in terms of combinatorics of Young diagrams and a simple criterion to determine the representation type for the finite quiver Hecke algebras of type $C_{\ell}^{(1)}$.

Representation Theory · Mathematics 2014-06-27 Susumu Ariki , Euiyong Park

Given a stratified variety X with strata satisfying a cohomological parity-vanishing condition, we define and show the uniqueness of "parity sheaves", which are objects in the constructible derived category of sheaves with coefficients in…

Representation Theory · Mathematics 2016-03-31 Daniel Juteau , Carl Mautner , Geordie Williamson

A Taylor variety consists of all fixed order Taylor polynomials of rational functions, where the number of variables and degrees of numerators and denominators are fixed. In one variable, Taylor varieties are given by rank constraints on…

Algebraic Geometry · Mathematics 2023-04-04 Aldo Conca , Simone Naldi , Giorgio Ottaviani , Bernd Sturmfels

We present an algorithm for the symbolic and numerical computation of the degrees of the Chern-Schwartz-MacPherson classes of a closed subvariety of projective space P^n. As the degree of the top Chern-Schwartz-MacPherson class is the…

Algebraic Geometry · Mathematics 2013-07-02 Christine Jost

Let X be a smooth proper variety over the quotient field of a Henselian discrete valuation ring with algebraically closed residue field of characteristic p. We show that for any coherent sheaf E on X, the index of X divides the…

Algebraic Geometry · Mathematics 2016-03-29 Hélène Esnault , Marc Levine , Olivier Wittenberg

We determine the number of ${\mathbb{F}}_q$-rational points of hyperplane sections of classical determinantal varieties defined by the vanishing of minors of a fixed size of a generic matrix, and identify sections giving the maximum number…

Combinatorics · Mathematics 2018-09-14 Peter Beelen , Sudhir R. Ghorpade

The goals of this article are as follows: (1) To determine the irreducible components of the affine varieties parametrizing the representations of $ \Lambda $ with dimension vector d, where $ \Lambda $ traces a major class of finite…

Representation Theory · Mathematics 2017-01-11 Birge Huisgen-Zimmermann , Ian Shipman

We study a class of determinantal ideals arising from conditional independence (CI) statements with hidden variables. Such CI statements translate into determinantal conditions on a matrix whose entries represent the probabilities of events…

Combinatorics · Mathematics 2025-10-15 Emiliano Liwski

We generalize type $A$ quivers to continuous type $A$ quivers and prove initial results about pointwise finite-dimensional (pwf) representations. We classify the indecomosable pwf representations and provide a decomposition theorem,…

Representation Theory · Mathematics 2025-06-19 Kiyoshi Igusa , Job D. Rock , Gordana Todorov

Motivated by the famous Skolem-Mahler-Lech theorem we initiate in this paper the study of a natural class of determinantal varieties which we call {\em Vandermonde varieties}. They are closely related to the varieties consisting of all…

Algebraic Geometry · Mathematics 2013-02-07 Ralf Fröberg , Boris Shapiro