English
Related papers

Related papers: Characterizing Van Kampen Squares via Descent Data

200 papers

We recall P. Balmer's definition of tensor triangular Chow group for a tensor triangulated category $\mathcal{K}$ and explore some of its properties. We give a proof that for a suitably nice scheme $X$ it recovers the usual notion of Chow…

Algebraic Geometry · Mathematics 2015-10-02 Sebastian Klein

Consider the functor describing deformations of a representation of the fundamental group of a variety X. This paper is chiefly concerned with establishing an analogue in finite characteristic of a result proved by Goldman and Millson for…

Algebraic Geometry · Mathematics 2019-07-04 J. P. Pridham

The fundamental construction underlying descent theory, the lax descent category, comes with a functor that forgets the descent data. We prove that, in any $2$-category $\mathfrak{A} $ with lax descent objects, the forgetful morphisms…

Category Theory · Mathematics 2021-05-21 Fernando Lucatelli Nunes

We make a comparative study of quadrature squeezing, photon-number distribution and Wigner function in a decayed quantum system. Specifically, for a field mode prepared initially in cat states interacting with a zero-temperature…

Quantum Physics · Physics 2015-05-28 Faisal A. A. El-Orany

At each iteration of a Block Coordinate Descent method one minimizes an approximation of the objective function with respect to a generally small set of variables subject to constraints in which these variables are involved. The…

Optimization and Control · Mathematics 2023-04-28 E. G. Birgin , J. M. Martínez

In this paper we examine numerically the properties, especially the scaling properties, of an isolated crescent singularity similar to that of a developable cone. The desired isolated crescent region is produced by applying six potential…

Soft Condensed Matter · Physics 2009-09-29 Tao Liang

With the help of various square principles, we obtain results concerning the consistency strength of several statements about trees containing ascent paths, special trees, and strong chain conditions. Building on a result that shows that…

Logic · Mathematics 2019-02-20 Chris Lambie-Hanson , Philipp Lücke

Capitalizing on recent work, that clarifies the consistent use of bosonization-debosonization methods to study Kondo-type quantum impurity models even in nonequilibrium settings, we revisit the compactification procedure of the two-channel…

Strongly Correlated Electrons · Physics 2024-08-09 Aleksandar Ljepoja , C. J. Bolech , Nayana Shah

We present a characterisation of a blender based on the topological alignment of certain sets in phase space in combination with cone conditions. Importantly, the required conditions can be verified by checking properties of a single…

Dynamical Systems · Mathematics 2024-10-15 Maciej J. Capiński , Bernd Krauskopf , Hinke M. Osinga , Piotr Zgliczyński

We investigate the properties of a class of piecewise-fractional maps arising from the introduction of an invariance under rescaling into convex quadratic maps. The subsequent maps are quasiconvex, and pseudoconvex on specific convex cones;…

Optimization and Control · Mathematics 2025-04-25 Alexandra Zverovich , Matthew Hutchings , Bertrand Gauthier

We study direct product representations of algebras in varieties. We collect several conditions expressing that these representations are "definable" in a first-order-logic sense, among them the concept of Definable Factor Congruences…

Logic · Mathematics 2009-06-25 Pedro Sánchez Terraf , Diego J. Vaggione

In this paper we propose a closed-system perspective to study decoherence. From this perspective we analyze the spin-bath model as presented in the literature, and a natural generalization of that model. On the basis of the results obtained…

Quantum Physics · Physics 2009-07-14 Mario Castagnino , Sebastian Fortin , Olimpia Lombardi

It is shown that the new formula for the field theory Poisson brackets arise naturally in the extension of the formal variational calculus incorporating divergences. The linear spaces of local functionals, evolutionary vector fields,…

Differential Geometry · Mathematics 2007-05-23 Vladimir O. Soloviev

A comprehensive account of the categorical properties of the category of small categories and asymmetric delta lenses is given in the recent works of Chollet et al. and Di Meglio. An important construction for proving many of these…

Category Theory · Mathematics 2023-08-01 Matthew Di Meglio

Hellsten \cite{MR2026390} proved that when $\kappa$ is $\Pi^1_n$-indescribable, the \emph{$n$-club} subsets of $\kappa$ provide a filter base for the $\Pi^1_n$-indescribability ideal, and hence can also be used to give a characterization of…

Logic · Mathematics 2020-01-31 Brent Cody , Victoria Gitman , Chris Lambie-Hanson

The null curvature condition (NCC) is the requirement that the Ricci curvature of a Lorentzian manifold be nonnegative along null directions, which ensures the focusing of null geodesic congruences. In this note, we show that the NCC…

General Relativity and Quantum Cosmology · Physics 2021-10-15 Åsmund Folkestad , Sergio Hernández-Cuenca

Given a contraction of a variety X to a base Y, we enhance the locus in Y over which the contraction is not an isomorphism with a certain sheaf of noncommutative rings D, under mild assumptions which hold in the case of (1) crepant partial…

Algebraic Geometry · Mathematics 2018-11-28 Will Donovan , Michael Wemyss

We investigate the behavior of four coherent-like conditions in regular conductor squares. In particular, we find necessary and sufficient conditions in order that a pullback ring be a finite conductor ring, a coherent ring, a generalized…

Commutative Algebra · Mathematics 2015-06-18 Jason Boynton , Sean Sather-Wagstaff

In self-supervised representation learning, a common idea behind most of the state-of-the-art approaches is to enforce the robustness of the representations to predefined augmentations. A potential issue of this idea is the existence of…

Machine Learning · Computer Science 2021-08-26 Tianyu Hua , Wenxiao Wang , Zihui Xue , Sucheng Ren , Yue Wang , Hang Zhao

Given functors $F,G:\mathcal C\to\mathcal D$ between small categories, when is it possible to say that $F$ can be "continuously deformed" into $G$ in a manner that is not necessarily reversible? In an attempt to answer this question in…

Category Theory · Mathematics 2015-11-02 Amit Kuber , David Wilding