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We show a Whitney Approximation Theorem for a continuous map from a manifold to a smooth CW complex. This enables us to show that a topological CW complex is homotopy equivalent to a smooth CW complex in a category of topological spaces. It…

Algebraic Topology · Mathematics 2022-08-12 Norio Iwase

In the sixties, Grothendieck developed the theory of pro-objects over a category. The fundamental property of the category $Pro(C)$ is that there is an embedding $C \stackrel{c}{\rightarrow} Pro(C)$, $Pro(C)$ is closed under small…

Category Theory · Mathematics 2020-10-22 Maria Emilia Descotte

We systematically study the moduli theory of symplectic varieties (in the sense of Beauville) which admit a resolution by an irreducible symplectic manifold. In particular, we prove an analog of Verbitsky's global Torelli theorem for the…

Algebraic Geometry · Mathematics 2021-01-07 Benjamin Bakker , Christian Lehn

In a multiplex network, a set of nodes is connected by different types of interactions, each represented as a separate layer within the network. Multiplexes have emerged as a key instrument for modeling large-scale complex systems, due to…

Probability · Mathematics 2025-10-13 Ankan Ganguly , Bhaswar B. Bhattacharya

The Quillen-McCord theorem (aka Quillen fiber lemma) gives a sufficient condition on a map between classifying spaces of posetal categories to be a homotopy equivalence. Jonathan Ariel Barmak in his paper [arXiv:1005.0538] gives an…

Algebraic Topology · Mathematics 2023-07-04 Vitalii Guzeev

We prove the conjecture that any Grothendieck $(\infty,1)$-topos can be presented by a Quillen model category that interprets homotopy type theory with strict univalent universes. Thus, homotopy type theory can be used as a formal language…

Algebraic Topology · Mathematics 2019-04-30 Michael Shulman

The optimal complexity of neural networks is achieved when the self-organization principles is used to eliminate the contradictions existing in accordance with the K. Godel theorem about incompleteness of the systems based on axiomatics.…

Neural and Evolutionary Computing · Computer Science 2007-05-23 V. Schetinin , A. Kostunin

In this paper we shall illustrate that each polytopal moment-angle complex can be understood as the intersection of the minima of corresponding Siegel leaves and the unit sphere, with respect to the maximum norm. Consequently, an…

Geometric Topology · Mathematics 2015-11-03 Li Cai

We introduce combinatorial types of arrangements of convex bodies, extending order types of point sets to arrangements of convex bodies, and study their realization spaces. Our main results witness a trade-off between the combinatorial…

Metric Geometry · Mathematics 2015-06-23 Michael Gene Dobbins , Andreas Holmsen , Alfredo Hubard

We develop an explicit covering theory for complexes of groups, parallel to that developed for graphs of groups by Bass. Given a covering of developable complexes of groups, we construct the induced monomorphism of fundamental groups and…

Group Theory · Mathematics 2007-10-04 Seonhee Lim , Anne Thomas

We describe the adjacency of vertices of the (unbounded version of the) set covering polyhedron, in a similar way to the description given by Chvatal for the stable set polytope. We find a sufficient condition for adjacency, and…

Combinatorics · Mathematics 2017-10-10 Néstor E. Aguilera , Ricardo D. Katz , Paola B. Tolomei

Inflation of a simplicial complex $K$ is a construction well known in combinatorial topology. It replaces each vertex $i$ of $K$ with a finite number $n_i$ of its copies, and each simplex $\{i_0,\ldots,i_k\}$ with $n_{i_0}n_{i_1}\cdots…

Algebraic Topology · Mathematics 2026-02-10 Anton Ayzenberg , Nadya Khoroshavkina

We give structural results about bifibrations of (internal) $(\infty,1)$-categories with internal sums. This includes a higher version of Moens' Theorem, characterizing cartesian bifibrations with extensive aka stable and disjoint internal…

Category Theory · Mathematics 2024-03-12 Jonathan Weinberger

In this revised form, the proof of the principal lemma has been simplified and the main theorem has been extended to all characteristics for those varieties which are smooth in codimension one. This principal theorem essentially says the…

alg-geom · Mathematics 2009-09-25 J. Alexander , A. Hirschowitz

We construct a nerve functor parametrized by a choice of quantale, exhibiting both the Vietoris-Rips complex and the magnitude nerve as instances of this nerve for different choices of monoidal structure on $\mathbb{R}$. Furthermore, the…

Algebraic Topology · Mathematics 2020-03-10 Simon Cho

We prove a version of the fundamental theorems of Morse Theory in the setting of finite spaces or partially ordered sets. By using these results we extend Forman's discrete Morse theory to more general cell complexes and derive the…

Through the study of Morse theory on the associated Milnor fiber, we show that complex hyperplane arrangement complements are minimal. That is, the complement of a complex hyperplane arrangement has the homotopy type of a CW complex in…

Algebraic Topology · Mathematics 2007-05-23 Richard Randell

We extend the Quillen Theorem Bn for homotopy fibers of Dwyer, et al. to similar results for homotopy pullbacks and note that these results imply similar results for zigzags in the categories of relative categories and k-relative…

Algebraic Topology · Mathematics 2013-01-22 C. Barwick , D. M. Kan

We prove a global version of the so-called div-curl-lemma, a crucial result for compensated compactness and in homogenization theory, for mixed tangential and normal boundary conditions in bounded weak Lipschitz domains in 3D and weak…

Analysis of PDEs · Mathematics 2018-12-18 Dirk Pauly

The recent paper "A quantitative Doignon-Bell-Scarf Theorem" by Aliev et al. generalizes the famous Doignon-Bell-Scarf Theorem on the existence of integer solutions to systems of linear inequalities. Their generalization examines the number…

Optimization and Control · Mathematics 2017-09-01 Stephen R. Chestnut , Robert Hildebrand , Rico Zenklusen