a groupoid object is both a generalization of a groupoid which is built on richer structures than sets, and a generalization of a group objects when...
5 KB (850 words) - 18:53, 8 December 2024
mathematics, an ∞-groupoid is an abstract homotopical model for topological spaces. One model uses Kan complexes which are fibrant objects in the category...
11 KB (1,667 words) - 05:23, 14 May 2025
In mathematics, a Lie groupoid is a groupoid where the set Ob {\displaystyle \operatorname {Ob} } of objects and the set Mor {\displaystyle \operatorname...
44 KB (7,436 words) - 07:45, 15 October 2024
homotopy theory, a groupoid (less often Brandt groupoid or virtual group) generalises the notion of group in several equivalent ways. A groupoid can be seen...
39 KB (6,232 words) - 06:39, 6 May 2025
algebras can be seen as a generalization of group objects to monoidal categories. Groupoid object internal category Awodey, Steve (2010), Category Theory...
6 KB (810 words) - 11:10, 22 April 2025
Magma (algebra) (redirect from Groupoid (algebra))
binary operation. The word groupoid is used by many universal algebraists, but workers in category theory and related areas object strongly to this usage...
18 KB (1,828 words) - 11:16, 17 April 2025
categories fibered in groupoids comes from groupoid objects internal to a category C {\displaystyle {\mathcal {C}}} . So given a groupoid object x ⇉ t s y {\displaystyle...
29 KB (5,041 words) - 00:21, 26 April 2025
constant sheaf. The fundamental groupoid of the singleton space is the trivial groupoid (a groupoid with one object * and one morphism Hom(*, *) = {...
9 KB (1,170 words) - 07:28, 24 April 2025
X\times G\to X,} we get the groupoid G {\displaystyle {\mathcal {G}}} (= a category whose morphisms are all invertible) where objects are elements of X {\displaystyle...
2 KB (344 words) - 14:11, 29 April 2025
theory, a branch of mathematics, an initial object of a category C is an object I in C such that for every object X in C, there exists precisely one morphism...
11 KB (1,336 words) - 16:25, 21 January 2024
Category (mathematics) (redirect from Object (category theory))
of category the only difference between groupoid and group is that a groupoid may have more than one object but the group must have only one. Consider...
21 KB (2,525 words) - 18:54, 19 March 2025
Inertia stack (redirect from Inertia groupoid)
groupoid. Then the inertia groupoid Λ U {\displaystyle \Lambda U} is a grouoiud (= a category whose morphisms are all invertible) where the objects are...
2 KB (273 words) - 19:51, 12 May 2025
case of monoid objects in the categories of small categories or of groupoids. Instead the notion of group object in the category of groupoids turns out to...
9 KB (1,415 words) - 16:43, 2 April 2025
Stack (mathematics) (redirect from Stack in groupoids)
stack in groupoids or a (2,1)-sheaf if it is also fibered in groupoids, meaning that its fibers (the inverse images of objects of C) are groupoids. Some...
34 KB (5,113 words) - 13:03, 2 April 2025
numbers object (NNO) is an object endowed with a recursive structure similar to natural numbers. More precisely, in a category E with a terminal object 1,...
7 KB (887 words) - 02:16, 27 January 2025
central groupoids are defined by an equational identity, they form a variety of algebras in which the free objects are called free central groupoids. Free...
8 KB (1,214 words) - 21:02, 14 April 2025
Higher-dimensional algebra (section Double groupoids)
invertible arrows, or morphisms. Double groupoids are often used to capture information about geometrical objects such as higher-dimensional manifolds (or...
17 KB (1,525 words) - 16:12, 4 May 2025
Orbifold (redirect from Orbifold groupoid)
charts and the gluing maps are isometries. Recall that a groupoid consists of a set of objects G 0 {\displaystyle G_{0}} , a set of arrows G 1 {\displaystyle...
78 KB (10,243 words) - 15:00, 14 March 2025
Category theory (redirect from Object of a category)
category is formed by two sorts of objects: the objects of the category, and the morphisms, which relate two objects called the source and the target of...
34 KB (3,893 words) - 07:51, 20 April 2025
(4) every groupoid object in X is effective. Mathematics portal Bousfield localization Homotopy hypothesis – Hypothesis that the ∞-groupoids are equivalent...
3 KB (338 words) - 06:40, 14 May 2025
double groupoid generalises the notion of groupoid and of category to a higher dimension. A double groupoid D is a higher-dimensional groupoid involving...
11 KB (1,536 words) - 23:06, 10 December 2024
a notion of homotopy: it is a unit interval object in the category of groupoids. The category of groupoids admits all colimits, and in particular all pushouts...
21 KB (3,373 words) - 16:41, 4 May 2025
Grothendieck's homotopy hypothesis states, homotopy theory speaking, that the ∞-groupoids are spaces. One version of the hypothesis was claimed to be proved in...
10 KB (1,259 words) - 05:21, 14 May 2025
Poisson manifold (redirect from Symplectic groupoid)
{\displaystyle T^{*}M} is not always integrable to a Lie groupoid. A symplectic groupoid is a Lie groupoid G ⇉ M {\displaystyle {\mathcal {G}}\rightrightarrows...
87 KB (12,662 words) - 01:05, 28 January 2025
Brown "Topology and Groupoids" pdf available Gives an account of some categorical methods in topology, use the fundamental groupoid on a set of base points...
13 KB (1,987 words) - 02:46, 12 January 2025
object or map object is the categorical generalization of a function space in set theory. Categories with all finite products and exponential objects...
8 KB (1,143 words) - 18:49, 9 October 2024
Group action (section Group actions and groupoids)
generally, it is an exponential object in the category of G-sets. The notion of group action can be encoded by the action groupoid G′ = G ⋉ X associated to the...
46 KB (5,742 words) - 03:09, 10 May 2025
Monodromy (section Monodromy groupoid and foliations)
Analogous to the fundamental groupoid it is possible to get rid of the choice of a base point and to define a monodromy groupoid. Here we consider (homotopy...
11 KB (1,692 words) - 06:00, 25 March 2025
to a different generalization of Lie groups, namely Lie groupoids, which are groupoid objects in the category of smooth manifolds with a further requirement...
65 KB (9,490 words) - 15:29, 22 April 2025
thought of as a "many-object generalisation" of a Lie algebra. Lie algebroids play a similar same role in the theory of Lie groupoids that Lie algebras play...
42 KB (7,376 words) - 16:57, 6 April 2025