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In this short note, we argue that directed homotopy can be given the structure of generalized modules, over particular monoids. This is part of a general attempt for refoundation of directed topology.

Algebraic Topology · Mathematics 2025-04-21 Eric Goubault

The Seifert-van Kampen theorem computes the fundamental group of a space from the fundamental groups of its constituents. We develop a modular SVK framework within the setting of computational paths - an approach to equality where witnesses…

Logic in Computer Science · Computer Science 2025-12-24 Arthur F. Ramos , Tiago M. L. de Veras , Ruy J. G. B. de Queiroz , Anjolina G. de Oliveira

The field of directed type theory seeks to design type theories capable of reasoning synthetically about (higher) categories, by generalizing the symmetric identity types of Martin-L\"of Type Theory to asymmetric hom-types. We articulate…

Category Theory · Mathematics 2025-10-21 Thorsten Altenkirch , Jacob Neumann

We investigate two approximation relations on a T0 topological space, the n-approximation, and the d-approximation, which are generalizations of the way-below relation on a dcpo. Different kinds of continuous spaces are defined by the two…

General Topology · Mathematics 2022-07-08 Yuxu Chen , Hui Kou , Zhenchao Lyu

We prove that the loop space of the directed suspension of a directed space is homotopy equivalent to the James construction. In particular, it does not depend on the directed structure of a given directed space.

Algebraic Topology · Mathematics 2016-07-05 Andrzej Weber , Krzysztof Ziemiański

Directed topology is a refinement of standard topology, where spaces may have non-reversible paths. It has been put forward as a candidate approach to the analysis of concurrent processes. Recently, a wealth of different frameworks for,…

General Topology · Mathematics 2012-12-06 André Hirschowitz , Michel Hirschowitz , Tom Hirschowitz

The study of equality types is central to homotopy type theory. Characterizing these types is often tricky, and various strategies, such as the encode-decode method, have been developed. We prove a theorem about equality types of…

Logic · Mathematics 2019-05-16 Nicolai Kraus , Jakob von Raumer

Category theory provides a means through which many far-ranging fields of mathematics can be related by their similar structure. In a paper by Robinson [2], this interconnectivity afforded by categorical perspectives allowed for the…

Algebraic Topology · Mathematics 2020-12-03 Karthik Boyareddygari

This paper studies a notion of directed homology for preordered spaces, called the homology digraph. We show that the homology digraph is a directed homotopy invariant and establish variants of the main results of ordinary singular homology…

Algebraic Topology · Mathematics 2023-12-06 Catarina Faustino , Thomas Kahl

Let $K$ be an arbitrary semi-cubical set that can be embedded in a standard cube. Using Discrete Morse Theory, we construct a CW-complex that is homotopy equivalent to the space $\vec{P}(K)_v^w$ of directed paths between two given vertices…

Algebraic Topology · Mathematics 2017-08-08 Krzysztof Ziemiański

The purpose of this paper is to collect the homotopical methods used in the development of the theory of flows initialized by author's paper ``A model category for the homotopy theory of concurrency''. It is presented generalizations of the…

Algebraic Topology · Mathematics 2007-07-11 Philippe Gaucher

For many years, there have been conducting research (e.g. by Bergelson, Furstenberg, Kojman, Kubi\'{s}, Shelah, Szeptycki, Weiss) into sequentially compact spaces that are, in a sense, topological counterparts of some combinatorial…

General Topology · Mathematics 2023-07-14 Rafał Filipów , Krzysztof Kowitz , Adam Kwela

Directed paths have been used by several authors to describe concurrent executions of a program. Spaces of directed paths in an appropriate state space contain executions with all possible legal schedulings. It is interesting to investigate…

Algebraic Topology · Mathematics 2023-06-22 Martin Raussen

Among plenty of applications, low-dimensional homogeneous spaces appear in cosmological models as both, classical factor spaces of multidimensional geometry and minisuperspaces in canonical quantization. Here a new tool to restrict their…

General Relativity and Quantum Cosmology · Physics 2016-08-31 M. Rainer

The paper establishes an equivalence between directed homotopy categories of (diagrams of) cubical sets and (diagrams of) directed topological spaces. This equivalence both lifts and extends an equivalence between classical homotopy…

Algebraic Topology · Mathematics 2026-02-02 Sanjeevi Krishnan

The paper addresses certain topological aspects of Dijkstra's PV-model for parallel computations in concurrency theory. The main result is a computation of the homology of the trace space associated with PV-programs in which access and…

Combinatorics · Mathematics 2016-11-28 Roy Meshulam , Martin Raussen

We discuss topological versions of the closed graph theorem, where continuity is inferred from near continuity in tandem with suitable conditions on source or target spaces. We seek internal characterizations of spaces satisfying a closed…

General Topology · Mathematics 2024-04-05 Dominikus Noll

Since Quillen proved his famous equivalences of homotopy categories in 1969, much work has been done towards classifying the rational homotopy types of simply connected topological places. The majority of this work has focused on rational…

Algebraic Topology · Mathematics 2015-12-15 Matthew Zawodniak

Many categories have been used to model concurrency. Using any of these, the challenge is to reduce a given model to a smaller representation which nevertheless preserves the relevant computer-scientific information. That is, one wants to…

Algebraic Topology · Mathematics 2009-04-27 Peter Bubenik

We study the problem of learning representations with controllable connectivity properties. This is beneficial in situations when the imposed structure can be leveraged upstream. In particular, we control the connectivity of an…

Machine Learning · Computer Science 2019-06-24 Christoph Hofer , Roland Kwitt , Mandar Dixit , Marc Niethammer