16 citations · 51 across the 15 of their papers we have counts for
16 papers
Stringy invariants for abelian character varieties
Carlos Florentino, Ángel González-Prieto, Alfonso Zamora
We compute all stringy invariants, encoding orbifold cohomology numbers, of (the normalization of) the identity component of -character varieties of free abelian groups and of m…
-polynomials of character varieties
Alfonso Zamora
These lecture notes contain the material presented at one of the mini-courses of the Workshop on Character Varieties and Higgs Bundles held in Liberia, Guanacaste, Costa Rica, in A…
Segre invariants of principal bundles over a curve
George H. Hitching, Alfonso Zamora
For a vector bundle over a curve , the Segre invariant encodes the maximal degree attained by rank subbundles of . The functions define stratification…
Root data in character varieties
Ángel González-Prieto, Alfonso Zamora
Given an algebraic reductive group over an algebraically closed field of characteristic zero and a finitely generated group, we provide a stratification of the -characte…
A guide to moduli theory beyond GIT
Tomás L. Gómez, Andres Fernández Herrero, Alfonso Zamora
In this survey we provide an overview of some recent developments in the construction of moduli spaces using stack-theoretic techniques. We will also explain the analogue of Harder…
The moduli stack of principal -sheaves and Gieseker-Harder-Narasimhan filtrations
Tomás L. Gómez, Andres Fernandez Herrero, Alfonso Zamora
Let X be a smooth projective variety and let G be a connected reductive group, both defined over a field of characteristic 0. Given a faithful representation of G into a produc…
On Hodge polynomials of Singular Character Varieties
Carlos Florentino, Azizeh Nozad, Jaime Silva +1
Let be the -character variety of , where is a complex reductive group and a finitely presented group. We introduce new techni…
Serre polynomials of - and -character varieties of free groups
Carlos Florentino, Azizeh Nozad, Alfonso Zamora
Let be a complex reductive group and denote the -character variety of the free group of rank . Using geometric methods, we prove that $E(\mathcal{X}_{r…
Generating series for the -polynomials of -character varieties
Carlos Florentino, Azizeh Nozad, Alfonso Zamora
With G=GL(n,C), let be the G-character variety of a given finitely presented group , and let be the locus of irred…
Generating sets for Clifford Algebras
Brian Sittinger, Ricardo Suárez, Alfonso Zamora
The aim of this paper is to find generating sets of commuting involutions and use them to explicitly construct minimal representations of Clifford algebras . By result…
Stability conditions and related filtrations for -constellations
Ronan Terpereau, Alfonso Zamora
Given an infinite reductive algebraic group , we consider -equivariant coherent sheaves with prescribed multiplicities, called -constellations, for which two stability…
On the Gieseker Harder-Narasimhan filtration for principal bundles
Indranil Biswas, Alfonso Zamora
We give an example of an orthogonal bundle where the Harder-Narasimhan filtration, with respect to Gieseker semistability, of its underlying vector bundle does not correspond to an…
GIT characterizations of Harder-Narasimhan filtrations
Alfonso Zamora
This Ph.D. thesis studies the relation between the Harder-Narasimhan filtration and a notion of GIT maximal unstability. When constructing a moduli space by using Geometric Invaria…
Harder-Narasimhan filtration for rank 2 tensors and stable coverings
Alfonso Zamora
We construct a Harder-Narasimhan filtration for rank tensors, where there does not exist any such notion a priori, as coming from a GIT notion of maximal unstability. The filtr…
On the Harder-Narasimhan filtration for finite dimensional representations of quivers
Alfonso Zamora
We prove that the Harder-Narasimhan filtration for an unstable finite dimensional representation of a finite quiver coincides with the filtration associated to the 1-parameter subg…
A GIT interpretration of the Harder-Narasimhan filtration
Tomas L. Gomez, Ignacio Sols, Alfonso Zamora
An unstable torsion free sheaf on a smooth projective variety gives a GIT unstable point in certain Quot scheme. To a GIT unstable point, Kempf associates a "maximally destabilizin…