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In this note we study the local projective model structure on presheaves of complexes on a site, i.e. we describe its classes of cofibrations, fibrations and weak equivalences. In particular, we prove that the fibrant objects are those…

Category Theory · Mathematics 2020-01-03 Utsav Choudhury , Martin Gallauer

Localic and realizability toposes are two central classes of toposes in categorical logic, both arising through the Hyland-Johnstone-Pitts tripos-to-topos construction. We investigate their shared geometric features by providing an…

Category Theory · Mathematics 2025-11-11 Maria Emilia Maietti , Davide Trotta

We introduce the notion of integrable connections for a sheaf of differential graded algebras on a topological space. We then describe them in the finite locally projective setting, when the sheaf is either the de Rham complex of a formal…

Algebraic Geometry · Mathematics 2025-02-05 Rubén Muñoz--Bertrand

We develop a theory of \emph{locally Frobenius algebras} which are colimits of certain directed systems of Frobenius algebras. A major goal is to obtain analogues of the work of Moore \& Peterson and Margolis on \emph{nearly Frobenius…

Rings and Algebras · Mathematics 2022-12-27 Andrew Baker

Understanding the shape and structure of objects is undoubtedly extremely important for object recognition, but the most common pattern recognition method currently used is machine learning, which often requires a large number of training…

Computer Vision and Pattern Recognition · Computer Science 2023-06-21 Wei Hui , Liping Yu , Yiran Wei

We give an internal description of constructible objects in an $\infty$-topos. More precisely, $P$-consctructible objects are locally constant objects internal to Fun($P$,An), for any noetherian poset $P$.

Category Theory · Mathematics 2025-10-30 Li He

The small objects in images and videos are usually not independent individuals. Instead, they more or less present some semantic and spatial layout relationships with each other. Modeling and inferring such intrinsic relationships can…

Computer Vision and Pattern Recognition · Computer Science 2020-09-03 Kui Fu , Jia Li , Lin Ma , Kai Mu , Yonghong Tian

In this work we shall introduce a new model structure on the category of pro-simplicial sheaves, which is very convenient for the study of \'etale homotopy. Using this model structure we define a pro-space associated to a topos, as a result…

Algebraic Topology · Mathematics 2015-12-03 Ilan Barnea , Tomer M. Schlank

Concave mirrors are fundamental optical elements, yet some easily observed behaviors are rarely addressed in standard textbooks, such as the formation of multiple reflected images. Here we investigate self-imaging -- where the observer is…

Optics · Physics 2025-12-30 Thach A. Nguyen , Kaitlyn S. Yasumura , Duy V. Tran , Trung V. Phan

In earlier work (arXiv:0801.0261), we gave a definition of an abelian category of motivic (constructible) sheaves over a base in characteristic zero using Nori's method. This category has Hodge and etale realizations, and is stable under…

Algebraic Geometry · Mathematics 2022-04-18 Donu Arapura

In this paper we introduce the notion of interval valued hesitant fuzzy soft topological space. Also the concepts of interval valued hesitant fuzzy soft closure, interior and neighbourhood are introduced here and established some important…

General Mathematics · Mathematics 2017-06-06 Manash Jyoti Borah , Bipan Hazarika

We investigate the connection between the spatiality of locale products and the earlier studies of the author on the locally fine coreflection of the products of uniform spaces. After giving a historical introduction and indicating the…

General Topology · Mathematics 2007-05-23 Aarno Hohti

We look at homotopy-coherent diagrams of spaces (after Segal, Leitch, Vogt, Mather, Cordier) over a Grothendieck site; we call these ``flexible presheaves''. After some preliminary materiel, we define the ``flexible sheaf'' condition. This…

q-alg · Mathematics 2008-02-03 Carlos Simpson

We study the homotopy theory of locally ordered spaces, that is manifolds with boundary whose charts are partially ordered in a compatible way. Their category is not particularly well-behaved with respect to colimits. However, this category…

Algebraic Topology · Mathematics 2009-12-21 Krzysztof Worytkiewicz

In this paper we introduce a notion of {\it generalized operad} containing as special cases various kinds of operad--like objects: ordinary, cyclic, modular, properads etc. We then construct inner cohomomorphism objects in their categories…

Category Theory · Mathematics 2011-01-10 D. Borisov , Yu. I. Manin

It is widely accepted that reasoning about object shape is important for object recognition. However, the most powerful object recognition methods today do not explicitly make use of object shape during learning. In this work, motivated by…

Computer Vision and Pattern Recognition · Computer Science 2021-06-22 Stefan Stojanov , Anh Thai , James M. Rehg

Any scheme has its associated little and big Zariski toposes. These toposes support an internal mathematical language which closely resembles the usual formal language of mathematics, but is "local on the base scheme": For example, from the…

Algebraic Geometry · Mathematics 2021-11-09 Ingo Blechschmidt

There is a well-established homotopy theory of simplicial objects in a Grothendieck topos, and folklore says that the weak equivalences are axiomatisable in the geometric fragment of $L_{\omega_1, \omega}$. We show that it is in fact a…

Category Theory · Mathematics 2014-05-01 Zhen Lin Low

We develop a theory of conically smooth stratified spaces and their smooth moduli, including a notion of classifying maps for tangential structures. We characterize continuous space-valued sheaves on these conically smooth stratified spaces…

Algebraic Topology · Mathematics 2017-02-10 David Ayala , John Francis , Hiro Lee Tanaka

We focus on the task of future frame prediction in video governed by underlying physical dynamics. We work with models which are object-centric, i.e., explicitly work with object representations, and propagate a loss in the latent space.…

Machine Learning · Computer Science 2021-07-19 Rushil Gupta , Vishal Sharma , Yash Jain , Yitao Liang , Guy Van den Broeck , Parag Singla