English
Related papers

Related papers: Stellar theory for flag complexes

200 papers

Let $E$ be an odd dimensional complex vector space and $\mbox{IF}:=\mbox{IF}(1,2;E)$ be the family of odd symplectic partial flag manifold. In this paper we give a full description of the irreducible components of the degree $d$ curve…

Algebraic Geometry · Mathematics 2025-02-25 Connor Bean , Bradley Cruikshank , Ryan M. Shifler

We develop a systematic method for computing the angle combinations at all vertices in an edge-to-edge tiling of the sphere by pentagons with the same five angles. The method is a useful and necessary step in many tiling problems about…

Metric Geometry · Mathematics 2023-09-27 Hoi Ping Luk , Min Yan

We introduce the notion of \textit{star cluster} of a simplex in a simplicial complex. This concept provides a general tool to study the topology of independence complexes of graphs. We use star clusters to answer a question arisen from…

Combinatorics · Mathematics 2010-07-05 Jonathan Ariel Barmak

We consider germs of holomorphic vector fields at the origin of $\mathbb{C}^3$, with non-isolated singularities that are tangent to a holomorphic foliation of codimension one. This configuration is known as a $2$-flag of foliations. The…

Dynamical Systems · Mathematics 2023-08-28 Fernando Lourenço , Eurípedes da Silva , Fernando Reis

The Union Closed Sets Conjecture is one of the most renowned problems in combinatorics. Its appeal lies in the simplicity of its statement contrasted with the potential complexity of its resolution. The conjecture posits that, in any union…

Combinatorics · Mathematics 2025-10-02 Nived J M

We introduce the notion of k-hyperclique complexes, i.e., the largest simplicial complexes on the set [n] with a fixed k-skeleton. These simplicial complexes are a higher-dimensional analogue of clique (or flag) complexes (case k=2) and…

Combinatorics · Mathematics 2007-10-14 Raul Cordovil , Manoel Lemos , Claudia Linhares Sales

We generalise partial results about the Yau-Tian-Donaldson correspondence on ruled manifolds to bundles whose fibre is a classical flag variety. This is done using Chern class computations involving the combinatorics of Schur functors. The…

Algebraic Geometry · Mathematics 2015-11-11 Anton Isopoussu

We prove the Ingram Conjecture, i.e., we show that the inverse limit spaces of every two tent maps with different slopes in the interval [1, 2] are non-homeomorphic. Based on the structure obtained from the proof, we also show that every…

Dynamical Systems · Mathematics 2014-11-11 M. Barge , H. Bruin , S. Štimac

We study the anisotropy theorem for Stanley-Reisner rings of simplicial homology spheres in characteristic 2 by Papadakis and Petrotou. This theorem implies the Hard Lefschetz theorem as well as McMullen's g-conjecture for such spheres. Our…

Combinatorics · Mathematics 2023-01-24 Kalle Karu , Elizabeth Xiao

We develop a general homological approach to presentations of connected graded associative algebras, and apply it to the loop homology of moment-angle complexes $Z_K$ that correspond to flag simplicial complexes $K$. For arbitrary…

Algebraic Topology · Mathematics 2025-12-24 Fedor Vylegzhanin

We construct a family of points on the Lagrangian cone of a partial flag bundle associated to a (possibly non-split) vector bundle from any Weyl-invariant $I$-function of a prequotient. This result can be seen as the nonabelian analogue of…

Algebraic Geometry · Mathematics 2026-02-11 Ionut Ciocan-Fontanine , Yuki Koto

A classical combinatorial fact is that the simplicial complex consisting of disjointly embedded chords in a convex planar polygon is a sphere. For any surface F with non-empty boundary, there is an analogous complex Arc(F) consisting of…

Geometric Topology · Mathematics 2007-05-23 R. C. Penner

We compute the coherent cohomology of the structure sheaf of complex periplectic Grassmannians. In particular, we show that it can be decomposed as a tensor product of the singular cohomology ring of a Grassmannian for either the symplectic…

Algebraic Geometry · Mathematics 2024-12-31 Steven V Sam , Andrew Snowden

Given a simplicial complex we associate to it a squarefree monomial ideal which we call the face ideal of the simplicial complex, and show that it has linear quotients. It turns out that its Alexander dual is a whisker complex. We apply…

Commutative Algebra · Mathematics 2014-11-25 Jürgen Herzog , Takayuki Hibi

In this note, we give Gysin formulas for partial flag bundles for the classical groups. We then give Gysin formulas for Schubert varieties in Grassmann bundles, including isotropic ones. All these formulas are proved in a rather uniform way…

Algebraic Geometry · Mathematics 2018-02-27 Lionel Darondeau , Piotr Pragacz

We first discuss the problems in the theory of ordinary differential equations that gave rise to the concept of a flag system and illustrate these with the Cartan criterion for Monge equations (1st order) as well as the Cartan statement…

Differential Geometry · Mathematics 2014-11-05 A. Kumpera

We study the double homology associated to triangulated spheres and present two results. First, we explicitly compute the double homology for minimum degree sphere triangulations. Using a spectral sequence argument, we compute the effect of…

Algebraic Topology · Mathematics 2024-07-02 Carlos Gabriel Valenzuela Ruiz

We construct a Legendrian version of Envelope theory. A tangential family is a 1-parameter family of rays emanating tangentially from a smooth plane curve. The Legendrian graph of the family is the union of the Legendrian lifts of the…

Differential Geometry · Mathematics 2007-05-23 Gianmarco Capitanio

We extend our theory of amorphous packings of hard spheres to binary mixtures and more generally to multicomponent systems. The theory is based on the assumption that amorphous packings produced by typical experimental or numerical…

Disordered Systems and Neural Networks · Physics 2015-05-13 Indaco Biazzo , Francesco Caltagirone , Giorgio Parisi , Francesco Zamponi

We introduce combinatorial objects named matricubes that provide a generalization of the theory of matroids. As matroids provide a combinatorial axiomatization of hyperplane arrangements, matricubes provide a combinatorial axiomatization of…

Combinatorics · Mathematics 2024-04-03 Omid Amini , Lucas Gierczak