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Related papers: Characterizations of modalities and lex modalities

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Given a small category C, we show that there is a universal way of expanding C into a model category, essentially by formally adjoining homotopy colimits. The technique of localization becomes a method for imposing `relations' into these…

Algebraic Topology · Mathematics 2007-05-23 Daniel Dugger

Fine shape, as defined by Melikhov, is an extension of the strong shape category of compacta (compact metrizable topological spaces) to all metrizable spaces, notable for being compatible with both \v{C}ech cohomology and Steenrod-Sitnikov…

General Topology · Mathematics 2025-10-16 Vladislav Zemlyanoy

We study the topology of a class of proper submodules and some of its distinguished subclasses and call them structure spaces. We give several criteria for the quasi-compactness of these structure spaces. We study $T_0$ and $T_1$ separation…

Rings and Algebras · Mathematics 2023-04-18 Amartya Goswami

We first establish several general properties of modality of algebraic group actions. In particular, we introduce the notion of a modality-regular action and prove that every visible action is modality-regular. Then, using these results, we…

Representation Theory · Mathematics 2017-07-26 Vladimir L. Popov

The notion of the \emph{homotopy type} of a topological stack has been around in the literature for some time. The basic idea is that an atlas $X \to \mathfrak{X}$ of a stack determines a topological groupoid $\mathbb{X}$ with object space…

Algebraic Topology · Mathematics 2009-01-22 Johannes Ebert

We introduce MTT, a dependent type theory which supports multiple modalities. MTT is parametrized by a mode theory which specifies a collection of modes, modalities, and transformations between them. We show that different choices of mode…

Logic in Computer Science · Computer Science 2023-06-22 Daniel Gratzer , G. A. Kavvos , Andreas Nuyts , Lars Birkedal

In this paper, we introduce relative LS category of a map and study some of its properties. Then we introduce `higher topological complexity' of a map, a homotopy invariant. We give a cohomological lower bound and compare it with previously…

Algebraic Topology · Mathematics 2020-12-15 Yuli B. Rudyak , Soumen Sarkar

Let X and Y be nonsingular real algebraic varieties, dimX>dimY-1. Assume that the variety Y is malleable, compact and connected. Our main result implies that each regular map from X to Y is homotopic to a surjective regular map. The class…

Algebraic Geometry · Mathematics 2023-02-07 Wojciech Kucharz

These notes contain a brief introduction to rational homotopy theory: its model category foundations, the Sullivan model and interactions with the theory of local commutative rings.

Algebraic Topology · Mathematics 2007-05-23 Kathryn Hess

Let $\mathscr{C}$ be a small category. For every commutative ring $R$ with unity, we associate an $R\mathrm{-linear}$ abelian category with the universal homotopy category of $\mathscr{C}$, where we can do the corresponding homological…

Algebraic Geometry · Mathematics 2024-01-03 Ahmad Rouintan

We give a new formulation of Turing reducibility in terms of higher modalities, inspired by an embedding of the Turing degrees in the lattice of subtoposes of the effective topos discovered by Hyland. In this definition, higher modalities…

Logic · Mathematics 2024-06-11 Andrew W Swan

In this paper we develop homotopy theoretical methods for studying diagrams. In particular we explain how to construct homotopy colimits and limits in an arbitrary model category. The key concept we introduce is that of a model…

Algebraic Topology · Mathematics 2009-09-25 Wojciech Chacholski , Jerome Scherer

We investigate algebraic and compositional properties of abstract multiway rewriting systems, which are archetypical structures underlying the formalism of the Wolfram model. We demonstrate the existence of higher homotopies in this class…

Category Theory · Mathematics 2021-11-29 Xerxes D. Arsiwalla , Jonathan Gorard , Hatem Elshatlawy

The first goal of this paper is to provide an abstract framework in which to formulate and study local duality in various algebraic and topological contexts. For any stable $\infty$-category $\mathcal{C}$ together with a collection of…

Algebraic Topology · Mathematics 2019-01-23 Tobias Barthel , Drew Heard , Gabriel Valenzuela

We examine subgroups of locally compact groups that are continuous homomorphic images of connected Lie groups and we give a criterion for being such an image. We also provide a new characterisation of Lie groups and a characterisation of…

General Topology · Mathematics 2024-07-02 Antoni Machowski

For a fixed ring, different classes of ring epimorphisms and localisation maps are compared. In fact, we provide sufficient conditions for a ring epimorphism to be a universal localisation. Furthermore, we consider recollements induced by…

Rings and Algebras · Mathematics 2012-07-20 Frederik Marks , Jorge Vitoria

We define the notion of a trace kernel on a manifold M. Roughly speaking, it is a sheaf on M x M for which the formalism of Hochschild homology applies. We associate a microlocal Euler class to such a kernel, a cohomology class with values…

Algebraic Geometry · Mathematics 2014-06-04 Masaki Kashiwara , Pierre Schapira

The eigenvalues of companion matrices associated with generalized Lucas sequences, denoted as L, exhibit a striking geometric resemblance to the Mandelbrot set M. This work investigates this connection by analyzing the statistical…

General Mathematics · Mathematics 2025-05-14 Arturo Ortiz-Tapia

We define and develop two-level type theory (2LTT), a version of Martin-L\"of type theory which combines two different type theories. We refer to them as the inner and the outer type theory. In our case of interest, the inner theory is…

Logic in Computer Science · Computer Science 2026-05-27 Danil Annenkov , Paolo Capriotti , Nicolai Kraus , Christian Sattler

We initiate the study of finite characterizations and exact learnability of modal languages. A finite characterization of a modal formula w.r.t. a set of formulas is a finite set of finite models (labelled either positive or negative) which…

Logic in Computer Science · Computer Science 2022-06-14 Balder ten Cate , Raoul Koudijs