English
Related papers

Related papers: Mustafin degenerations

200 papers

Let $M$ be a holomorphically symplectic manifold, equipped with a Lagrangian fibration $\pi:\; M \to X$. A degenerate twistor deformation (sometimes also called ``a Tate-Shafarevich twist'') is a family of holomorphically symplectic…

Algebraic Geometry · Mathematics 2025-10-17 Fedor Bogomolov , Ljudmila Kamenova , Misha Verbitsky

PBW degenerations are a particularly nice family of flat degenerations of type A flag varieties. We show that the cohomology of any PBW degeneration of the flag variety surjects onto the cohomology of the original flag variety, and that…

Representation Theory · Mathematics 2017-10-31 Martina Lanini , Elisabetta Strickland

We construct a family of flat semitoric degenerations for the Hibi variety of every finite distributive lattice. The irreducible components of each degeneration are the toric varieties associated with polytopes forming a regular subdivision…

Algebraic Geometry · Mathematics 2021-12-16 Evgeny Feigin , Igor Makhlin

Given a toric degeneration (a degeneration to a toric variety), over the complex numbers, we construct a surjective continuous map from a general fiber to the special fiber of the degeneration in the classical topology. The construction is…

Algebraic Geometry · Mathematics 2025-11-04 Takuya Murata , Lara Bossinger

In this thesis we study toric degenerations of projective varieties. We compare different constructions to understand how and why they are related as s first step towards developing a global framework. In focus are toric degenerations…

Algebraic Geometry · Mathematics 2018-06-07 Lara Bossinger

We investigate when the tangent bundle of a projective manifold has a non-trivial first order (or positive-dimensional) deformation. This leads to a new conjectural characterization of the complex projective space.

Algebraic Geometry · Mathematics 2020-07-20 Thomas Peternell

We investigate degenerations of syzygy bundles on plane curves over $p$-adic fields. We use Mustafin varieties which are degenerations of projective spaces to find a large family of models of plane curves over the ring of integers such that…

Algebraic Geometry · Mathematics 2019-07-05 Marvin Anas Hahn , Annette Werner

The term degenerate is used to describe abelian varieties whose Hodge rings contain exceptional cycles -- Hodge cycles that are not generated by divisor classes. We can see the effect of the exceptional cycles on the structure of an abelian…

Number Theory · Mathematics 2024-08-02 Heidi Goodson

We study toric degenerations arising from Gr\"obner degenerations or the tropicalization of partial flag varieties. We produce a new family of toric degenerations of partial flag varieties whose combinatorics are governed by matching fields…

Algebraic Geometry · Mathematics 2023-10-12 Oliver Clarke , Fatemeh Mohammadi , Francesca Zaffalon

This paper studies affine Deligne-Lusztig varieties in the affine flag manifold of a split group. Among other things, it proves emptiness for certain of these varieties, relates some of them to those for Levi subgroups, extends previous…

Algebraic Geometry · Mathematics 2014-01-14 Ulrich Goertz , Thomas J. Haines , Robert E. Kottwitz , Daniel C. Reuman

This paper provides a unified combinatorial framework to study orbits in certain affine flag varieties via the associated Bruhat-Tits buildings. We first formulate, for arbitrary affine buildings, the notion of a chimney retraction. This…

Representation Theory · Mathematics 2022-04-08 Elizabeth Milićević , Yusra Naqvi , Petra Schwer , Anne Thomas

We develop a novel theory of one-parameter families of multi-view varieties. These families are induced by quotient lattices over discrete valuation rings and generalise the notion of \textit{Mustafin varieties}. We study the geometry and…

Algebraic Geometry · Mathematics 2020-10-14 Marvin Anas Hahn

We show that a weight variety, which is a quotient of a flag variety by the maximal torus, admits a flat degeneration to a toric variety. In particular, we show that the moduli spaces of spatial polygons degenerate to polarized toric…

Algebraic Geometry · Mathematics 2007-05-23 Philip Foth , Yi Hu

In the framework of the problem of characterizing complete flag manifolds by their contractions, the complete flags of type $F_4$ and $G_2$ satisfy the property that any possible tower of Bott-Samelson varieties dominating them birationally…

Algebraic Geometry · Mathematics 2022-02-24 Gianluca Occhetta , Luis E. Solá Conde

Building on the theory of parity sheaves due to Juteau-Mautner-Williamson, we develop a formalism of "mixed modular perverse sheaves" for varieties equipped with a stratification by affine spaces. We then give two applications: (1) a…

Representation Theory · Mathematics 2016-02-10 Pramod N. Achar , Simon Riche

Mechanical metamaterials are periodic lattice structures with complex unit cell architectures that can achieve extraordinary mechanical properties beyond the capability of bulk materials. A new class of metamaterials is proposed, whose…

Applied Physics · Physics 2022-07-22 Marius Wagner , Fabian Schwarz , Nick Huber , Lena Geistlich , Henning Galinski , Ralph Spolenak

We compute toric degenerations arising from the tropicalization of the full flag varieties $\mathcal{F}\ell_4$ and $\mathcal{F}\ell_5$ embedded in a product of Grassmannians. For $\mathcal{F}\ell_4$ and $\mathcal{F}\ell_5$ we compare toric…

Algebraic Geometry · Mathematics 2018-02-06 Lara Bossinger , Sara Lamboglia , Kalina Mincheva , Fatemeh Mohammadi

This paper surveys and gives a uniform exposition of results contained in papers published by the team of authors. The subject is degenerations of surfaces, especially to unions of planes. More specifically, we deduce some properties of the…

Algebraic Geometry · Mathematics 2008-05-09 Alberto Calabri , Ciro Ciliberto , Flaminio Flamini , Rick Miranda

In this paper we study the Bruhat decomposition of not necessarily connected reductive quasi-split groups $G$ with respect to not necessarily connected parabolic subgroups. If $G$ is defined over a finite field, we construct a smooth…

Algebraic Geometry · Mathematics 2013-12-25 Torsten Wedhorn

In this paper we study the degeneration of convex real projective structures on bordered surfaces.

Geometric Topology · Mathematics 2018-12-13 Inkang Kim