Permutohedral complex and complements of diagonal subspace arrangements

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Panov, Taras, Tril, Vsevolod
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917277231742976
author Panov, Taras
Tril, Vsevolod
author_facet Panov, Taras
Tril, Vsevolod
contents The complement of an arrangement of diagonal subspaces $x_{i_1} = \cdots = x_{i_k}$ in the real space is defined by a simplicial complex $K$. In this paper, we prove that the complement of a diagonal subspace arrangement is homotopy equivalent to a subcomplex $\mathrm{Perm}(K)$ of faces of the permutohedron. The product in the cohomology ring of the complement of a diagonal arrangement is then described via Saneblidze and Umble's cellular approximation of the diagonal map in the permutohedron. We consider the projection from the permutohedron to the cube and prove that the Saneblidze-Umble diagonal maps to the diagonal constructed by Li Cai for describing the product in the cohomology of a real moment-angle complex.
format Preprint
id arxiv_https___arxiv_org_abs_2504_04183
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Permutohedral complex and complements of diagonal subspace arrangements
Panov, Taras
Tril, Vsevolod
Algebraic Topology
57S12, 14N20, 55N45, 57T30
The complement of an arrangement of diagonal subspaces $x_{i_1} = \cdots = x_{i_k}$ in the real space is defined by a simplicial complex $K$. In this paper, we prove that the complement of a diagonal subspace arrangement is homotopy equivalent to a subcomplex $\mathrm{Perm}(K)$ of faces of the permutohedron. The product in the cohomology ring of the complement of a diagonal arrangement is then described via Saneblidze and Umble's cellular approximation of the diagonal map in the permutohedron. We consider the projection from the permutohedron to the cube and prove that the Saneblidze-Umble diagonal maps to the diagonal constructed by Li Cai for describing the product in the cohomology of a real moment-angle complex.
title Permutohedral complex and complements of diagonal subspace arrangements
topic Algebraic Topology
57S12, 14N20, 55N45, 57T30
url https://arxiv.org/abs/2504.04183