6 papers
Stability and disconnected groups
Andres Fernandez Herrero, Andrés Ibáñez Núñez
We study the notion of semistability for principal bundles over curves with possibly disconnected reductive structure group. We establish a new characterization of the behavior of…
Intrinsic Donaldson-Thomas theory. II. Stability measures and invariants
Chenjing Bu, Andrés Ibáñez Núñez, Tasuki Kinjo
This is the second paper in a series on intrinsic Donaldson-Thomas theory, a framework for studying the enumerative geometry of general algebraic stacks. In this paper, we present…
Intrinsic Donaldson-Thomas theory. I. Component lattices of stacks
Chenjing Bu, Daniel Halpern-Leistner, Andrés Ibáñez Núñez +1
This is the first paper in a series on intrinsic Donaldson-Thomas theory, where we develop a new framework for enumerative geometry that allows the generalization of constructions…
Cohomology of symmetric stacks
Chenjing Bu, Ben Davison, Andrés Ibáñez Núñez +2
We construct decompositions of: (1) the cohomology of smooth stacks, (2) the Borel--Moore homology of -shifted symplectic stacks, and (3) the vanishing cycle cohomology of $(-1)…
Refined Harder-Narasimhan filtrations in moduli theory
Andrés Ibáñez Núñez
We define canonical refinements of Harder-Narasimhan filtrations and stratifications in moduli theory, generalising and relating work of Haiden-Katzarkov-Kontsevich-Pandit and Kirw…
Relative étale slices and cohomology of moduli spaces
Mark Andrea de Cataldo, Andres Fernandez Herrero, Andrés Ibáñez Núñez
We use techniques of Alper-Hall-Rydh to prove a local structure theorem for smooth morphisms between smooth stacks around points with linearly reductive stabilizers. This implies t…