English
Related papers

Related papers: On face numbers of flag simplicial complexes

200 papers

Let $A$ be a Cartan matrix and $G(A)$ be the Kac-Moody group associated to Cartan matrix $A$. In this paper, we discuss the computation of the rank $i_k$ of homotopy group $\pi_k(G(A))$. For a large class of Kac-Moody groups, we construct…

Algebraic Topology · Mathematics 2015-01-20 Zhao Xu-an , Jin Chunhua

We study d-dimensional generalizations of three mutually related topics in graph theory: Hamiltonian paths, (unit) interval graphs, and binomial edge ideals. We provide partial high-dimensional generalizations of Ore and Posa's sufficient…

Combinatorics · Mathematics 2021-04-13 Bruno Benedetti , Lisa Seccia , Matteo Varbaro

One of the most common and effective methods of obtaining structural information on simplicial complexes is to use tools from algebraic geometry/commutative algebra (often motivated by properties of toric varieties). However, there is no…

Combinatorics · Mathematics 2025-11-04 Soohyun Park

We present explicit constructions of centrally symmetric polytopes with many faces: first, we construct a d-dimensional centrally symmetric polytope P with about (1.316)^d vertices such that every pair of non-antipodal vertices of P spans…

Metric Geometry · Mathematics 2011-11-21 Alexander Barvinok , Seung Jin Lee , Isabella Novik

A tautological system, introduced in \cite{LSY}\cite{LY}, arises as a regular holonomic system of partial differential equations that govern the period integrals of a family of complete intersections in a complex manifold $X$, equipped with…

Algebraic Geometry · Mathematics 2013-02-20 Spencer Bloch , An Huang , Bong H. Lian , Vasudevan Srinivas , Shing-Tung Yau

We discuss the `hd-compactification' of a semi-simple Lie group to a manifold with corners; it is the real analog of the wonderful compactification of deConcini and Procesi. There is a 1-1 correspondence between the boundary faces of the…

Differential Geometry · Mathematics 2019-10-08 Pierre Albin , Panagiotis Dimakis , Richard Melrose , David Vogan

The antiprism triangulation provides a natural way to subdivide a simplicial complex $\Delta$, similar to barycentric subdivision, which appeared independently in combinatorial algebraic topology and computer science. It can be defined as…

Combinatorics · Mathematics 2021-09-07 Christos A. Athanasiadis , Jan-Marten Brunink , Martina Juhnke-Kubitzke

It will be proved that a $k$-clique in the $1$-skeleton of either the order polytope or the chain polytope corresponds to the $(k-1)$-face, which is a simplex, in each polytope. These results generalize the known explicit descriptions of…

Combinatorics · Mathematics 2025-09-11 Aki Mori

Let $M$ be a closed triangulable manifold, and let $\Delta$ be a triangulation of $M$. What is the smallest number of vertices that $\Delta$ can have? How big or small can the number of edges of $\Delta$ be as a function of the number of…

Combinatorics · Mathematics 2015-05-26 Steven Klee , Isabella Novik

We describe a provably complete algorithm for the generation of a tight, possibly exact superset of all combinatorially distinct simple n-facet polytopes in R^d, along with their graphs, f-vectors, and face lattices. The technique applies…

Combinatorics · Mathematics 2009-08-13 Sandeep Koranne , Anand Kulkarni

Regular polygonal complexes in euclidean 3-space are discrete polyhedra-like structures with finite or infinite polygons as faces and with finite graphs as vertex-figures, such that their symmetry groups are transitive on the flags. The…

Combinatorics · Mathematics 2012-10-09 Daniel Pellicer , Egon Schulte

We count and give a parametrization of connected components in the space of flags transverse to a given transverse pair in every flag varieties of $\mathrm{SO}_0(p,q)$. We compute the effect the involution of the unipotent radical has on…

Differential Geometry · Mathematics 2025-12-04 Clarence Kineider , Roméo Troubat

This article gives a natural decomposition of the suspension of generalized moment-angle complexes or {\it partial product spaces} which arise as {\it polyhedral product functors} described below. In the special case of the complements of…

Algebraic Topology · Mathematics 2008-12-09 A. Bahri , M. Bendersky , F. R. Cohen , S. Gitler

We derive tight expressions for the maximum number of $k$-faces, $0\le k\le d-1$, of the Minkowski sum, $P_1+P_2+P_3$, of three $d$-dimensional convex polytopes $P_1$, $P_2$ and $P_3$, as a function of the number of vertices of the…

Computational Geometry · Computer Science 2012-11-27 Menelaos I. Karavelas , Christos Konaxis , Eleni Tzanaki

The $g$-theorem is a momentous result in combinatorics that gives a complete numerical characterization of the face numbers of simplicial convex polytopes. The $g$-conjecture asserts that the same numerical conditions given in the…

Combinatorics · Mathematics 2024-07-02 Kai Fong Ernest Chong , Tiong Seng Tay

We prove that certain conditions on multigraded Betti numbers of a simplicial complex $K$ imply existence of a higher Massey product in cohomology of a moment-angle-complex $\mathcal Z_K$, which contains a unique element (a strictly defined…

Algebraic Topology · Mathematics 2018-08-29 Ivan Limonchenko

We extend the notion of face rings of simplicial complexes and simplicial posets to the case of finite-length (possibly infinite) simplicial posets with a group action. The action on the complex induces an action on the face ring, and we…

Combinatorics · Mathematics 2021-11-30 Alessio D'Alì , Emanuele Delucchi

Brenti and Welker have shown that for any simplicial complex X, the face vectors of successive barycentric subdivisions of X have roots which converge to fixed values depending only on the dimension of X. We improve and generalize this…

Combinatorics · Mathematics 2011-10-13 Emanuele Delucchi , Aaron Pixton , Lucas Sabalka

In this paper, we determine the homotopy type of the quotient space $\mathcal{Z}_{\Delta^k_m}/S^1_d$, given by the moment-angle complex $\mathcal{Z}_{\Delta_m^k}$ under the diagonal circle action.

Algebraic Topology · Mathematics 2019-12-10 Xin Fu

While faces of a polytope form a well structured lattice, in which faces of each possible dimension are present, this is not true for general compact convex sets. We address the question of what dimensional patterns are possible for the…

Metric Geometry · Mathematics 2017-03-23 Vera Roshchina , Tian Sang , David Yost