Search Results: Homotopy groups
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Homotopy
Selasa, 2026-05-26 23:29:24being called a homotopy (/həˈmɒtəpiː/ hə-MOT-ə-pee; /ˈhoʊmoʊˌtoʊpiː/ HOH-moh-toh-pee) between the two functions. A notable use of homotopy is the definition...
Click to read more »Homotopy type theory
Sabtu, 2026-05-02 12:13:19In mathematical logic and computer science, homotopy type theory (HoTT) includes various lines of development of intuitionistic type theory, based on the...
Click to read more »Homotopy groups of spheres
Selasa, 2026-05-26 14:59:19In the mathematical field of algebraic topology, the homotopy groups of spheres describe how spheres of various dimensions can wrap around each other....
Click to read more »Homotopy group
Senin, 2026-03-23 04:10:54In mathematics, homotopy groups are used in algebraic topology to classify topological spaces. The first and simplest homotopy group is the fundamental...
Click to read more »Homotopy category
Selasa, 2025-08-19 18:24:36In mathematics, the homotopy category is a category built from the category of topological spaces which in a sense identifies two spaces that have the...
Click to read more »Homotopy sphere
Rabu, 2025-02-05 04:42:25branch of mathematics, a homotopy sphere is an n-manifold that is homotopy equivalent to the n-sphere. It thus has the same homotopy groups and the same homology...
Click to read more »Homotopy theory
Jumat, 2026-03-20 12:26:44In mathematics, homotopy theory is a systematic study of situations in which maps can come with homotopies between them. It originated as a topic in algebraic...
Click to read more »Homotopy principle
Rabu, 2026-04-15 00:51:28In mathematics, the homotopy principle (or h-principle) is a very general way to solve partial differential equations (PDEs), and more generally partial...
Click to read more »Algebraic homotopy
Selasa, 2024-09-10 06:01:52In mathematics, algebraic homotopy is a research program on homotopy theory proposed by J.H.C. Whitehead in his 1950 ICM talk, where he described it as:...
Click to read more »Fundamental group
Minggu, 2026-05-10 23:49:06is the first and simplest homotopy group. The fundamental group is a homotopy invariant—topological spaces that are homotopy equivalent (or the stronger...
Click to read more »Rational homotopy theory
Kamis, 2026-05-14 16:42:14topology, rational homotopy theory is a simplified version of homotopy theory for topological spaces, in which all torsion in the homotopy groups is ignored...
Click to read more »A¹ homotopy theory
Senin, 2026-03-09 22:14:37mathematics, A1 homotopy theory or motivic homotopy theory is a way to apply the techniques of algebraic topology, specifically homotopy, to algebraic varieties...
Click to read more »Homotopy category of chain complexes
Jumat, 2025-10-03 19:51:26mathematics, the homotopy category K(A) of chain complexes in an additive category A is a framework for working with chain homotopies and homotopy equivalences...
Click to read more »Homotopy hypothesis
Jumat, 2026-04-24 07:12:29category theory, a branch of mathematics, Grothendieck's homotopy hypothesis states, homotopy-theoretically speaking, that the ∞-groupoids are spaces....
Click to read more »Algebraic topology
Kamis, 2026-05-28 01:03:43topological spaces up to homeomorphism, though usually most classify up to homotopy equivalence. Although algebraic topology primarily uses algebra to study...
Click to read more »Fibration
Senin, 2026-01-19 13:04:07{\displaystyle p\colon E\to B} satisfies the homotopy lifting property for a space X {\displaystyle X} if: for every homotopy h : X × [ 0 , 1 ] → B {\displaystyle...
Click to read more »Spectrum (topology)
Minggu, 2026-05-10 08:54:34technical difficulties, but they all determine the same homotopy category, known as the stable homotopy category. This is one of the key points for introducing...
Click to read more »Simplicial homotopy
Kamis, 2025-06-19 08:29:01In algebraic topology, a simplicial homotopy is an analog of a homotopy between topological spaces for simplicial sets. Precisely,pg 23 if f , g : X →...
Click to read more »Homotopy colimit and limit
Selasa, 2026-04-07 12:23:54algebraic topology, the homotopy limit and colimitpg 52 are variants of the notions of limit and colimit extended to the homotopy category Ho ( Top ) {\displaystyle...
Click to read more »Simple-homotopy equivalence
Jumat, 2022-07-29 16:04:36topology, a simple-homotopy equivalence is a refinement of the concept of homotopy equivalence. Two CW-complexes are simple-homotopy equivalent if they...
Click to read more »Homotopy Lie algebra
Rabu, 2026-02-04 13:00:03In mathematics, in particular abstract algebra and topology, a homotopy Lie algebra (or L ∞ {\displaystyle L_{\infty }} -algebra) is a generalisation of...
Click to read more »Homotopy dimension
Sabtu, 2026-01-03 00:45:07In mathematics, especially algebraic topology, the homotopy dimension of a topological space does not have a fixed meaning. However, it can refer to the...
Click to read more »Homotopy to Marie
Sabtu, 2026-06-06 21:17:46Homotopy to Marie is the fifth album by Nurse with Wound, released in 1982. Although Nurse with Wound had generated considerable interest across their...
Click to read more »Regular homotopy
Senin, 2025-12-15 05:06:34of topology, a regular homotopy refers to a special kind of homotopy between immersions of one manifold in another. The homotopy must be a 1-parameter...
Click to read more »Stable homotopy theory
Minggu, 2026-02-22 05:19:55In mathematics, stable homotopy theory is the part of homotopy theory (and thus algebraic topology) concerned with all structure and phenomena that remain...
Click to read more »Homotopy lifting property
Jumat, 2026-02-06 20:46:46In mathematics, in particular in homotopy theory within algebraic topology, the homotopy lifting property (also known as an instance of the right lifting...
Click to read more »Chromatic homotopy theory
Senin, 2025-09-01 11:06:03In mathematics, chromatic homotopy theory is a subfield of stable homotopy theory that studies complex-oriented cohomology theories from the "chromatic"...
Click to read more »Numerical algebraic geometry
Jumat, 2026-05-29 00:59:30computational method used in numerical algebraic geometry is homotopy continuation, in which a homotopy is formed between two polynomial systems, and the isolated...
Click to read more »Nerve (category theory)
Sabtu, 2026-06-06 04:41:54Since simplicial sets have a good homotopy theory, one can ask questions about the meaning of the various homotopy groups πn(N(C)). One hopes that the...
Click to read more »Homotopy analysis method
Jumat, 2026-05-01 01:03:29The homotopy analysis method (HAM) is a semi-analytical technique to solve nonlinear ordinary/partial differential equations. The homotopy analysis method...
Click to read more »Homotopy extension property
Selasa, 2025-08-19 18:24:45the homotopy extension property indicates which homotopies defined on a subspace can be extended to a homotopy defined on a larger space. The homotopy extension...
Click to read more »Homeomorphism
Minggu, 2026-05-17 10:54:05deformations, such as the homeomorphism between a trefoil knot and a circle. Homotopy and isotopy are precise definitions for the informal concept of continuous...
Click to read more »Higher category theory
Sabtu, 2026-05-30 10:23:17category theory is often applied in algebraic topology (especially in homotopy theory), where one studies algebraic invariants of spaces, such as the...
Click to read more »Retraction (topology)
Sabtu, 2026-04-25 04:37:26For example, every topological manifold is an ANR. Every ANR has the homotopy type of a very simple topological space, a CW complex. Let X be a topological...
Click to read more »Simplicial set
Senin, 2026-03-16 10:59:42purposes of homotopy theory. Specifically, the category of simplicial sets carries a natural model structure, and the corresponding homotopy category is...
Click to read more »Topology
Jumat, 2026-06-05 00:01:57The deformations that are considered in topology are homeomorphisms and homotopies. A property that is invariant under such deformations is a topological...
Click to read more »Blakers–Massey theorem
Jumat, 2026-05-01 11:56:07Blakers and William S. Massey, gave vanishing conditions for certain triad homotopy groups of spaces. This connectivity result may be expressed more precisely...
Click to read more »Haskell
Senin, 2026-04-13 12:13:22Haskell (/ˈhæskəl/) is a general-purpose, statically typed, purely functional programming language with type inference and lazy evaluation. Haskell pioneered...
Click to read more »Stokes' theorem
Minggu, 2026-05-03 06:28:49or "homotopy"; the latter omit condition [TLH3]. So from now on we refer to homotopy (homotope) in the sense of theorem 2-1 as a tubular homotopy (resp...
Click to read more »Dustin Clausen
Minggu, 2026-05-31 17:05:58His research interests include the intersections of number theory and homotopy theory. Dustin Clausen completed his undergraduate studies at Harvard University...
Click to read more »CW complex
Kamis, 2026-05-07 00:54:28It was initially introduced by J. H. C. Whitehead to meet the needs of homotopy theory. CW complexes have better categorical properties than simplicial...
Click to read more ȃtale homotopy type
Kamis, 2026-05-14 21:32:58mathematics, especially in algebraic geometry, the étale homotopy type is an analogue of the homotopy type of topological spaces for algebraic varieties. Roughly...
Click to read more »Derived category
Kamis, 2026-04-30 23:30:27terms. A parallel development was the category of spectra in homotopy theory. The homotopy category of spectra and the derived category of a ring are both...
Click to read more »Homotopy fiber
Senin, 2026-04-06 17:05:34In mathematics, especially homotopy theory, the homotopy fiber (sometimes called the mapping fiber) is part of a construction that associates a fibration...
Click to read more »Weak equivalence (homotopy theory)
Minggu, 2026-05-31 16:42:03In mathematics, a weak equivalence is a notion from homotopy theory that in some sense identifies objects that have the same "shape". This notion is formalized...
Click to read more »Obstruction theory
Sabtu, 2025-11-15 10:26:55constructing a section of a bundle. The older meaning for obstruction theory in homotopy theory relates to the procedure, inductive with respect to dimension, for...
Click to read more »Sphere eversion
Sabtu, 2026-02-21 07:28:33surprising, both to non-mathematicians and to those who understand regular homotopy, and can be regarded as a veridical paradox; that is something that, while...
Click to read more »Singular homology
Selasa, 2026-05-05 21:07:59the chain complex. The resulting homology groups are the same for all homotopy equivalent spaces, which is the reason for their study. These constructions...
Click to read more »Immersion (mathematics)
Sabtu, 2026-04-25 06:50:48regular homotopy is thus a homotopy through immersions. Hassler Whitney initiated the systematic study of immersions and regular homotopies in the 1940s...
Click to read more »Zhouli Xu
Rabu, 2026-04-29 10:30:46at the University of California, Los Angeles, known for computations of homotopy groups of spheres. Xu earned both his B.S. and M.S. in mathematics from...
Click to read more »Roman Mikhaylov
Kamis, 2026-04-30 07:04:43and independent filmmaker. He is a specialist in homological algebra, homotopy theory, and group theory. He was an invited speaker at the 7th European...
Click to read more »Homotopy category of an ∞-category
Sabtu, 2026-05-02 11:29:13In mathematics, especially category theory, the homotopy category of an ∞-category C is the category where the objects are those in C but the hom-set from...
Click to read more »Homotopy associative algebra
Kamis, 2026-04-16 10:45:02that are associative only up to homotopy, and the A∞ structure keeps track of these homotopies, homotopies of homotopies, and so forth. They are ubiquitous...
Click to read more »Dold–Thom theorem
Jumat, 2026-03-20 12:30:38In algebraic topology, the Dold-Thom theorem states that the homotopy groups of the infinite symmetric product of a connected CW complex are the same as...
Click to read more »Eilenberg–MacLane space
Sabtu, 2026-03-07 21:31:45Eilenberg–MacLane space is a topological space with a single nontrivial homotopy group. Let G be a group and n a positive integer. A connected topological...
Click to read more »J. H. C. Whitehead
Selasa, 2026-04-14 22:41:26as "Henry", was a British mathematician and was one of the founders of homotopy theory. He was born in Chennai (then known as Madras), in India, and died...
Click to read more »Puppe sequence
Selasa, 2024-12-03 20:47:38In mathematics, the Puppe sequence is a construction of homotopy theory, so named after Dieter Puppe. It comes in two forms: a long exact sequence, built...
Click to read more »Ring spectrum
Rabu, 2024-03-27 01:29:52In stable homotopy theory, a ring spectrum is a spectrum E together with a multiplication map μ: E ∧ E → E and a unit map η: S → E, where S is the sphere...
Click to read more »Bott periodicity theorem
Jumat, 2026-03-27 01:02:40mathematics, the Bott periodicity theorem describes a periodicity in the homotopy groups of classical groups, discovered by Raoul Bott (1957, 1959), which...
Click to read more »Hurewicz theorem
Senin, 2025-11-10 16:32:05the Hurewicz theorem is a basic result of algebraic topology, connecting homotopy theory with homology theory via a map known as the Hurewicz homomorphism...
Click to read more »Cofibration
Jumat, 2026-03-20 12:29:16particular homotopy theory, a continuous mapping between topological spaces i : A → X {\displaystyle i:A\to X} is a cofibration if it has the homotopy extension...
Click to read more »Tutte homotopy theorem
Jumat, 2025-11-21 08:46:26In mathematics, Tutte's homotopy theorem, introduced by Tutte (1958), generalises the concept of "path" from graphs to matroids, and states roughly that...
Click to read more »Sphere spectrum
Selasa, 2024-07-30 15:36:49In stable homotopy theory, a branch of mathematics, the sphere spectrum S is the monoidal unit in the category of spectra. It is the suspension spectrum...
Click to read more »Path (topology)
Senin, 2025-01-13 23:55:10also define paths and loops in pointed spaces, which are important in homotopy theory. If X {\displaystyle X} is a topological space with basepoint x...
Click to read more »Homotopy excision theorem
Rabu, 2021-05-12 03:47:59In algebraic topology, the homotopy excision theorem offers a substitute for the absence of excision in homotopy theory. More precisely, let ( X ; A ...
Click to read more »H-space
Sabtu, 2026-04-04 21:55:06In mathematics, an H-space is a homotopy-theoretic version of a generalization of the notion of topological group, in which the axioms on associativity...
Click to read more »Mapping cone (topology)
Jumat, 2025-07-18 07:55:35In mathematics, especially homotopy theory, the mapping cone is a construction in topology analogous to a quotient space and denoted C f {\displaystyle...
Click to read more »Coherency (homotopy theory)
Rabu, 2026-04-22 06:33:47in homotopy theory and (higher) category theory, coherency is the standard that equalities or diagrams must satisfy when they hold "up to homotopy" or...
Click to read more »Directed algebraic topology
Jumat, 2025-06-20 04:37:42directed analogues of homotopy equivalence. For example, homotopy groups and fundamental n-groupoids of spaces generalize to homotopy monoids and fundamental...
Click to read more »Fundamental groupoid
Sabtu, 2025-07-19 08:48:55widely-known fundamental group; as such, it captures information about the homotopy type of a topological space. In terms of category theory, the fundamental...
Click to read more »Borel conjecture
Selasa, 2026-05-05 21:35:06conjecture, asserting that a weak, algebraic notion of equivalence (namely, homotopy equivalence) should imply a stronger, topological notion (namely, homeomorphism)...
Click to read more »Seifert–Van Kampen theorem
Minggu, 2026-03-15 09:50:07of nonabelian second relative homotopy groups, and in fact of homotopy 2-types. The second part applies a Higher Homotopy van Kampen Theorem for crossed...
Click to read more »Fiber-homotopy equivalence
Jumat, 2026-03-20 12:30:58a fiber-homotopy equivalence is a map over a space B that has homotopy inverse over B (that is if h t {\displaystyle h_{t}} is a homotopy between the...
Click to read more »Rational homotopy sphere
Rabu, 2025-08-20 00:48:31topology, a rational homotopy n {\displaystyle n} -sphere is an n {\displaystyle n} -dimensional manifold with the same rational homotopy groups as the n {\displaystyle...
Click to read more »Whitehead torsion
Jumat, 2025-06-13 18:00:40the obstruction to a homotopy equivalence f : X → Y {\displaystyle f\colon X\to Y} of finite CW-complexes being a simple homotopy equivalence is its Whitehead...
Click to read more »Product
Senin, 2025-12-01 19:41:13Look up product in Wiktionary, the free dictionary. Product may refer to: Product (business), an item that can be offered to a market to satisfy the desire...
Click to read more »Universal bundle
Sabtu, 2025-12-06 03:59:48BG. When the definition of the classifying space takes place within the homotopy category of CW complexes, existence theorems for universal bundles arise...
Click to read more »Mackey functor
Jumat, 2026-03-20 12:25:40that generalizes various constructions in group theory and equivariant homotopy theory. Named after American mathematician George Mackey, these functors...
Click to read more »Lens space
Selasa, 2025-11-11 05:39:15of closed manifolds whose homeomorphism type is not determined by their homotopy type. J. W. Alexander in 1919 showed that the lens spaces L ( 5 ; 1 ) {\displaystyle...
Click to read more »Whitehead theorem
Minggu, 2026-04-19 19:42:35In homotopy theory (a branch of mathematics), the Whitehead theorem states that if a continuous mapping f between CW complexes X and Y induces isomorphisms...
Click to read more »Complex projective space
Minggu, 2026-05-17 10:22:53isomorphism of homotopy groups is described below, and the isomorphism of homotopy groups is a standard calculation in stable homotopy theory (which can...
Click to read more »Localization of a category
Kamis, 2026-02-19 10:41:16before. In homotopy theory, for example, there are many examples of mappings that are invertible up to homotopy; and so large classes of homotopy equivalent...
Click to read more »Emily Riehl
Rabu, 2025-12-17 10:17:10American mathematician who has contributed to higher category theory and homotopy theory. Much of her work, including her PhD thesis, concerns model structures...
Click to read more »Simple homotopy theory
Rabu, 2026-03-18 19:38:58mathematics, simple homotopy theory is a homotopy theory (a branch of algebraic topology) that concerns with the simple-homotopy type of a space. It was...
Click to read more »Timeline of bordism
Senin, 2026-04-13 06:37:07orientable manifold to be a boundary. 1958 Frank Adams Adams spectral sequence to calculate, potentially, stable homotopy groups from cohomology groups....
Click to read more »Vladimir Voevodsky
Selasa, 2026-04-14 05:20:26September 2017) was a Russian-American mathematician. His work in developing a homotopy theory for algebraic varieties and formulating motivic cohomology led to...
Click to read more »Model category
Sabtu, 2025-04-26 06:20:18In mathematics, particularly in homotopy theory, a model category is a category with distinguished classes of morphisms ('arrows') called 'weak equivalences'...
Click to read more »Topological defect
Selasa, 2026-05-26 08:00:53which is explained by having the soliton belong to a different topological homotopy class or cohomology class than the base physical system. More simply: it...
Click to read more »Moore space (algebraic topology)
Selasa, 2025-08-19 22:46:39the Eilenberg–Maclane spaces of homotopy theory, in the sense that it has only one nonzero homology (rather than homotopy) group. The study of Moore spaces...
Click to read more »Euler characteristic
Rabu, 2026-04-22 06:32:24Homology is a topological invariant, and moreover a homotopy invariant: Two topological spaces that are homotopy equivalent have isomorphic homology groups. It...
Click to read more »Classifying space
Jumat, 2026-03-20 12:11:47In mathematics, specifically in homotopy theory, a classifying space BG of a topological group G is the quotient of a weakly contractible space EG (i.e...
Click to read more »Simplicial group
Jumat, 2026-05-22 02:00:07abelian groups. A simplicial group is a Kan complex (in particular, its homotopy groups make sense). The Dold–Kan correspondence says that a simplicial...
Click to read more »Chain complex
Rabu, 2025-10-29 16:56:33spaces. In the case of singular homology, a homotopy between continuous maps f, g : X → Y induces a chain homotopy between the chain maps corresponding to...
Click to read more »NLab
Selasa, 2026-02-17 14:35:45philosophy with a focus on methods from type theory, category theory, and homotopy theory. The nLab espouses the "n-point of view" (a deliberate pun on Wikipedia's...
Click to read more »Thorsten Altenkirch
Rabu, 2026-04-15 13:34:36University of Nottingham known for his research on logic, type theory, and homotopy type theory. Altenkirch was part of the 2012/2013 special year on univalent...
Click to read more »Compact-open topology
Jumat, 2026-01-02 08:49:21of the commonly used topologies on function spaces, and is applied in homotopy theory and functional analysis. It was introduced by Ralph Fox in 1945...
Click to read more »Topos
Senin, 2026-04-27 00:59:52associated to the site underlying a topos a pro-simplicial set (up to homotopy). (It's better to consider it in Ho(pro-SS); see Edwards) Using this inverse...
Click to read more »Orthogonal group
Selasa, 2026-05-26 00:21:57the homotopy groups stabilize, and πk(O(n + 1)) = πk(O(n)) for n > k + 1: thus the homotopy groups of the stable space equal the lower homotopy groups...
Click to read more »Pseudocircle
Rabu, 2025-08-20 00:30:27y)=(0,-1)\end{cases}}} is a weak homotopy equivalence; that is, f {\displaystyle f} induces an isomorphism on all homotopy groups. It follows that f {\displaystyle...
Click to read more »Morse theory
Sabtu, 2025-09-06 16:34:06{\displaystyle 0<a<f(q),} then M a {\displaystyle M^{a}} is a disk, which is homotopy equivalent to a point (a 0-cell) which has been "attached" to the empty...
Click to read more »Symmetric product (topology)
Jumat, 2026-03-20 19:03:13symmetric product. This construction can easily be extended to give a homotopy functor. From an algebraic point of view, the infinite symmetric product...
Click to read more »Cellular approximation theorem
Minggu, 2026-02-08 22:35:56already cellular on a subcomplex A of X, then we can furthermore choose the homotopy to be stationary on A. From an algebraic topological viewpoint, any map...
Click to read more »Representation up to homotopy
Selasa, 2026-04-07 07:22:16A representation up to homotopy has several meanings. One of the earliest appeared in physics, in constrained Hamiltonian systems. The essential idea is...
Click to read more »Peter Hilton
Minggu, 2026-05-17 12:50:54November 2010) was a British mathematician, noted for his contributions to homotopy theory and for code-breaking during World War II. He was born in Brondesbury...
Click to read more »De Rham cohomology
Rabu, 2026-06-03 22:29:20{\displaystyle d} restricted to closed forms has a local inverse called a homotopy operator. Since it is also nilpotent, it forms a dual chain complex with...
Click to read more »Derived algebraic geometry
Jumat, 2026-04-03 20:26:40{\displaystyle E_{\infty }} -ring spectra from algebraic topology, whose higher homotopy groups account for the non-discreteness (e.g., Tor) of the structure sheaf...
Click to read more »Michael J. Hopkins
Minggu, 2026-03-08 05:50:30University. Hopkins' work concentrates on algebraic topology, especially stable homotopy theory. It can roughly be divided into four parts (while the list of topics...
Click to read more »Exotic sphere
Jumat, 2026-05-29 12:38:44group Θ n {\displaystyle \Theta _{n}} of h-cobordism classes of oriented homotopy n-spheres, which is finite and abelian. In dimension 4 almost nothing is...
Click to read more »Generalized Poincaré conjecture
Jumat, 2026-05-29 12:37:07generalized Poincaré conjecture is a statement that a manifold that is a homotopy sphere is a sphere. More precisely, one fixes a category of manifolds:...
Click to read more »Configuration space (mathematics)
Kamis, 2025-09-04 12:59:04configuration space of two points in R n {\displaystyle \mathbf {R} ^{n}} is homotopy equivalent to the sphere S n − 1 {\displaystyle S^{n-1}} . The configuration...
Click to read more »Jack Morava
Minggu, 2025-11-09 05:19:47American mathematician at Johns Hopkins University. Morava specialized in homotopy theory and is credited for Morava K-theory, a class of cohomology theories...
Click to read more »Milnor's theorem on Kan complexes
Sabtu, 2025-09-27 09:10:45geometric realization functor from the homotopy category of the category Kan of Kan complexes to the homotopy category of the category Top of (reasonable)...
Click to read more »Quasi-category
Sabtu, 2026-05-30 10:24:52other by higher order invertible morphisms (2-simplices thought of as "homotopies"). These higher order morphisms can also be composed, but again the composition...
Click to read more »Surgery theory
Kamis, 2025-10-16 09:29:56some desired property, in such a way that the effects on the homology, homotopy groups, or other invariants of the manifold are known. A relatively easy...
Click to read more »Type theory
Kamis, 2026-05-28 13:17:58is an active area of research, one direction being the development of homotopy type theory. The first computer proof assistant, called Automath, used...
Click to read more »Glossary of algebraic topology
Jumat, 2026-06-05 12:54:21in glossary of topology are generally omitted. Abstract homotopy theory and motivic homotopy theory are also outside the scope. Glossary of category theory...
Click to read more »Equivariant stable homotopy theory
Minggu, 2019-03-17 23:06:20In mathematics, more specifically in topology, the equivariant stable homotopy theory is a subfield of equivariant topology that studies a spectrum with...
Click to read more »J-homomorphism
Jumat, 2025-04-04 08:54:36the J-homomorphism is a mapping from the homotopy groups of the special orthogonal groups to the homotopy groups of spheres. It was defined by George...
Click to read more »A∞-operad
Rabu, 2025-07-16 08:43:36mathematics, an A∞-operad is a type of operad used in algebraic topology and homotopy theory to describe algebraic structures where the property of associativity...
Click to read more »Jacob Lurie
Kamis, 2026-06-04 15:59:07Fellowship. Lurie's research interests are algebraic geometry, topology, and homotopy theory. When he was a student in the Science, Mathematics, and Computer...
Click to read more »Tomer Schlank
Rabu, 2026-04-15 22:51:10was a professor at Hebrew University of Jerusalem. He primarily works in homotopy theory, algebraic geometry, and number theory. In 2022 he won the Erdős...
Click to read more »Dennis Sullivan
Sabtu, 2026-05-09 13:48:19created rational homotopy theory in the late 1960s and 1970s. It examines "rationalizations" of simply connected topological spaces with homotopy groups and...
Click to read more »Highly structured ring spectrum
Kamis, 2024-08-01 00:15:21ring spectrum or A ∞ {\displaystyle A_{\infty }} -ring is an object in homotopy theory encoding a refinement of a multiplicative structure on a cohomology...
Click to read more »Daniel Quillen
Sabtu, 2026-06-06 18:06:23higher algebraic K-theory in 1972. This new tool, formulated in terms of homotopy theory, proved to be successful in formulating and solving problems in...
Click to read more »Homotopical connectivity
Kamis, 2025-10-16 06:54:54connectivity is based on the homotopy groups of the space. A space is n-connected (or n-simple connected) if its first n homotopy groups are trivial. Homotopical...
Click to read more »Kuiper's theorem
Sabtu, 2026-05-30 23:23:00Kuiper's theorem, is that this group is weakly contractible, ie. all its homotopy groups are trivial. This result has important uses in topological K-theory...
Click to read more »Homology (mathematics)
Sabtu, 2026-05-09 06:32:20group. The nth homotopy group π n ( X ) {\displaystyle \pi _{n}(X)} of a topological space X {\displaystyle X} is the group of homotopy classes of basepoint-preserving...
Click to read more »Eckmann–Hilton argument
Selasa, 2026-03-17 08:27:52monoid. This can then be used to prove the commutativity of the higher homotopy groups. The principle is named after Beno Eckmann and Peter Hilton, who...
Click to read more »Kan–Quillen model structure
Selasa, 2025-04-29 04:12:47all Kan complexes and it furthermore models the homotopy theory of CW complexes up to weak homotopy equivalence, with the correspondence between simplicial...
Click to read more »Chromatic spectral sequence
Selasa, 2026-05-12 00:17:43cohomology, which is in turn used for calculating the stable homotopy groups of spheres. Chromatic homotopy theory Adams-Novikov spectral sequence p-local spectrum...
Click to read more »Hopf invariant
Kamis, 2024-09-26 13:38:38mathematics, in particular in algebraic topology, the Hopf invariant is a homotopy invariant of certain maps between n-spheres. In 1931 Heinz Hopf used Clifford...
Click to read more »Quillen's theorems A and B
Sabtu, 2026-05-09 06:31:25be homotopy equivalent. Quillen's Theorem B gives a sufficient condition for a square consisting of classifying spaces of categories to be homotopy Cartesian...
Click to read more »Surgery exact sequence
Rabu, 2026-05-13 20:44:19which classifies n {\displaystyle n} -dimensional manifolds within the homotopy type of X {\displaystyle X} . The basic idea is that in order to calculate...
Click to read more »∞-groupoid
Kamis, 2026-03-19 02:31:56morphism is an isomorphism. The homotopy hypothesis states that ∞-groupoids are equivalent to spaces up to homotopy. Alexander Grothendieck suggested...
Click to read more »Morava K-theory
Selasa, 2026-05-12 00:17:53In stable homotopy theory, a branch of mathematics, Morava K-theory is one of a collection of cohomology theories introduced in algebraic topology by Jack...
Click to read more »Atiyah–Segal completion theorem
Sabtu, 2023-08-19 13:22:26completion theorem is a theorem in mathematics about equivariant K-theory in homotopy theory. Let G be a compact Lie group and let X be a G-CW-complex. The theorem...
Click to read more »Pursuing Stacks
Minggu, 2025-03-30 14:22:11about 600 pages of research notes. The topic of the work is a generalized homotopy theory using higher category theory. The word "stacks" in the title refers...
Click to read more »Clark Barwick
Kamis, 2026-03-19 02:00:25mathematics at the University of Edinburgh. His research is centered around homotopy theory, algebraic K-theory, higher category theory, and related areas....
Click to read more »Functor
Jumat, 2026-04-24 05:06:37fundamental group based at x0, denoted π1(X, x0). This is the group of homotopy classes of loops based at x0, with the group operation of concatenation...
Click to read more »Adams spectral sequence
Sabtu, 2026-02-28 23:35:01called stable homotopy theory. It is a reformulation using homological algebra, and an extension, of a technique called 'killing homotopy groups' applied...
Click to read more »Freudenthal suspension theorem
Sabtu, 2024-09-28 09:42:00field of homotopy theory, the Freudenthal suspension theorem is the fundamental result leading to the concept of stabilization of homotopy groups and...
Click to read more »Daniel Kan
Selasa, 2026-05-12 00:05:53August 4, 2013) was a Dutch mathematician working in category theory and homotopy theory. He was a prolific contributor to both fields for six decades, having...
Click to read more »Hilton's theorem
Jumat, 2024-12-27 14:42:18Peter Hilton (1955), states that the loop space of a wedge of spheres is homotopy-equivalent to a product of loop spaces of spheres. John Milnor (1972) showed...
Click to read more »Ambient isotopy
Kamis, 2025-08-21 07:16:33Springer-Verlag, 1983 Sasho Kalajdzievski, An Illustrated Introduction to Topology and Homotopy, CRC Press, 2010, Chapter 10: Isotopy and Homotopy v t e...
Click to read more »Homology, Homotopy and Applications
Senin, 2025-12-22 02:23:26Homology, Homotopy and Applications is a peer-reviewed delayed open access mathematics journal published by International Press. It was established in...
Click to read more »Brown's representability theorem
Minggu, 2025-12-07 01:47:09representability theorem in homotopy theory gives necessary and sufficient conditions for a contravariant functor F on the homotopy category Hotc of pointed...
Click to read more »Homotopical algebra
Minggu, 2024-06-23 21:54:55the fact that a common approach to such generalizations is via abstract homotopy theory, as in nonabelian algebraic topology, and in particular the theory...
Click to read more »Lefschetz hyperplane theorem
Senin, 2025-07-14 23:21:20projective space and a hyperplane section Y, the homology, cohomology, and homotopy groups of X determine those of Y. A result of this kind was first stated...
Click to read more »Hopf theorem
Minggu, 2020-10-11 00:44:44differential topology, saying that the topological degree is the only homotopy invariant of continuous maps to spheres. Let M be an n-dimensional compact...
Click to read more »Diffeomorphism
Selasa, 2026-04-28 07:27:56{\displaystyle g>1} have the homotopy-type of their mapping class groups (i.e. the components are contractible). The homotopy-type of the diffeomorphism...
Click to read more »Spanier–Whitehead duality
Jumat, 2026-03-27 03:59:19In mathematics, Spanier–Whitehead duality is a duality theory in homotopy theory, based on a geometrical idea that a topological space X may be considered...
Click to read more »Douglas Ravenel
Selasa, 2026-05-12 00:39:49Oswald Veblen Prize in Geometry. Ravenel's main area of work is stable homotopy theory. Two of his most famous papers are Periodic phenomena in the Adams–Novikov...
Click to read more »Mark Mahowald
Minggu, 2026-03-08 01:01:38Evanston, Illinois. Much of Mahowald's most important works concerns the homotopy groups of spheres, especially using the Adams spectral sequence at the...
Click to read more »Crossed module
Senin, 2026-01-19 07:15:44In mathematics, and especially in homotopy theory, a crossed module consists of groups G {\displaystyle G} and H {\displaystyle H} , where G {\displaystyle...
Click to read more »Mapping space
Sabtu, 2026-05-02 06:58:53{\displaystyle h:I\to \operatorname {Map} (X,Y)} in the mapping space is exactly a homotopy between the starting point and the end point. From the category theory...
Click to read more »Cohomology
Selasa, 2026-05-19 13:08:28K ( A , j ) {\displaystyle K(A,j)} whose j-th homotopy group is isomorphic to A and whose other homotopy groups are zero. Such a space is called an Eilenberg–MacLane...
Click to read more »Quasi-fibration
Jumat, 2026-03-20 12:30:21→ B having the same behaviour as a fibration regarding the (relative) homotopy groups of E, B and p−1(x). Equivalently, one can define a quasifibration...
Click to read more »Loop space
Kamis, 2026-02-19 16:27:39is, the multiplication is homotopy-coherently associative. The set of path components of ΩX, i.e. the set of based-homotopy equivalence classes of based...
Click to read more »7
Selasa, 2026-05-26 10:32:35A. (ed.). "Sequence A001676 (Number of h-cobordism classes of smooth homotopy n-spheres.)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation...
Click to read more »EHP spectral sequence
Jumat, 2023-02-17 03:29:36spectral sequence is a spectral sequence used for inductively calculating the homotopy groups of spheres localized at some prime p. It is described in more detail...
Click to read more »Winding number
Sabtu, 2026-04-25 06:35:20circle. The set of homotopy classes of maps from a circle to a topological space form a group, which is called the first homotopy group or fundamental...
Click to read more »Category theory
Minggu, 2026-05-17 07:12:23Introduction to Category Theory, ISBN 978-0521283045. Simpson, Carlos (2010). Homotopy theory of higher categories. arXiv:1001.4071. Bibcode:2010arXiv1001.4071S...
Click to read more »Convergence space
Sabtu, 2025-11-29 21:32:59set-theoretic continuum Pointless Algebraic combinatorial homology cohomology homotopy Differential Geometric low-dimensional knot Digital Key concepts Open set /...
Click to read more »Algebraic K-theory
Jumat, 2026-06-05 03:37:12simple homotopy equivalence is a finer invariant than homotopy equivalence by introducing an invariant called the torsion. The torsion of a homotopy equivalence...
Click to read more »Eilenberg–MacLane spectrum
Selasa, 2026-05-12 00:18:03category D ( Z ) {\displaystyle D(\mathbb {Z} )} of abelian groups in the homotopy category of spectra. In addition, these spectra can be used to construct...
Click to read more »Hiroshi Toda
Selasa, 2026-03-03 02:27:182026)) was a Japanese mathematician, who specialized in stable and unstable homotopy theory. He started publishing in 1952. Many of his early papers are concerned...
Click to read more »Coarse structure
Jumat, 2026-05-15 10:31:19set-theoretic continuum Pointless Algebraic combinatorial homology cohomology homotopy Differential Geometric low-dimensional knot Digital Key concepts Open set /...
Click to read more »Isotopy
Kamis, 2021-12-23 17:28:29Homotopy#Isotopy, a continuous path of homeomorphisms connecting two given homeomorphisms is an isotopy of the two given homeomorphisms in homotopy Regular...
Click to read more »Normal invariant
Sabtu, 2026-03-21 00:04:30a normal map on X endows the space, roughly speaking, with some of the homotopy-theoretic global structure of a closed manifold. In particular, X has a...
Click to read more »Kan fibration
Minggu, 2026-05-17 14:04:21conjectured that the homotopy category of geometric realizations of infinity groupoids is equivalent to the homotopy category of homotopy types. This is called...
Click to read more »Characteristic class
Kamis, 2026-04-09 10:46:00that implied in the homotopy category a mapping from X to a classifying space BG, for the relevant linear group G. For the homotopy theory the relevant...
Click to read more »Final topology
Selasa, 2026-05-12 09:18:49set-theoretic continuum Pointless Algebraic combinatorial homology cohomology homotopy Differential Geometric low-dimensional knot Digital Key concepts Open set /...
Click to read more »Covering space
Selasa, 2026-05-05 02:57:02since all coverings have the homotopy lifting property, covering spaces are an important tool in the calculation of homotopy groups. A standard example...
Click to read more »Minimal fibration
Selasa, 2025-07-01 03:39:34In mathematics, especially homotopy theory, a minimal fibration is used to approximate fibrations between presheaves. A minimal fibration has a defining...
Click to read more »Pi
Jumat, 2026-06-05 10:58:27uses Morera's theorem, which implies that the integral is invariant under homotopy of the curve, so that it can be deformed to a circle and then integrated...
Click to read more »Univalent foundations
Rabu, 2026-06-03 07:18:49but they may be thought of as spaces, with equal types corresponding to homotopy equivalent spaces and with equal elements of a type corresponding to points...
Click to read more »Postnikov system
Selasa, 2026-03-31 02:25:55In homotopy theory, a branch of algebraic topology, a Postnikov system (or Postnikov tower) is a way of decomposing a topological space by filtering its...
Click to read more »Michael Shulman (mathematician)
Selasa, 2025-06-17 06:15:20of San Diego who works in category theory and higher category theory, homotopy theory, logic as applied to set theory, and computer science. Shulman did...
Click to read more »Smale conjecture
Jumat, 2024-05-10 04:05:29is the statement that the diffeomorphism group of the 3-sphere has the homotopy-type of its isometry group, the orthogonal group O(4). It was proved in...
Click to read more »Kervaire–Milnor group
Selasa, 2025-07-01 01:19:30Kervaire–Milnor group is an abelian group defined as the h-cobordism classes of homotopy spheres with the connected sum as composition and the reverse orientation...
Click to read more »Fixed-point computation
Sabtu, 2025-12-27 18:05:58restart algorithm. B. Curtis Eaves presented the homotopy method, based on the concept of homotopy. Given a function f, for which we want to find a fixed...
Click to read more »Interior product
Senin, 2026-05-18 16:01:33forms by the Cartan formula (also known as the Cartan identity, Cartan homotopy formula or Cartan magic formula): L X ω = d ( ι X ω ) + ι X d ω = { d ...
Click to read more »H-cobordism
Minggu, 2026-05-10 08:51:20homotopy equivalence) if the inclusion maps M ↪ W and N ↪ W {\displaystyle M\hookrightarrow W\quad {\mbox{and}}\quad N\hookrightarrow W} are homotopy...
Click to read more »Link concordance
Senin, 2022-10-24 15:07:13relation. It is weaker than isotopy, and stronger than homotopy: isotopy implies concordance implies homotopy. A link is a slice link if it is concordant to the...
Click to read more »Kirsten Wickelgren
Senin, 2026-02-02 00:23:02Ph.D. in 2009. Her dissertation, Lower Central Series Obstructions To Homotopy Sections of Curves Over Number Fields, was supervised by Gunnar Carlsson...
Click to read more »Degree of a continuous mapping
Rabu, 2026-02-18 06:38:55manifolds was first defined by Brouwer, who showed that the degree is homotopy invariant and used it to prove the Brouwer fixed point theorem. Less general...
Click to read more »Spherical cow
Jumat, 2026-06-05 10:28:45A GIF of a homotopy from a spherical cow to a less spherical one...
Click to read more »Timelike homotopy
Minggu, 2023-10-29 05:23:29curves are distinguished as timelike. A timelike homotopy between two timelike curves is a homotopy such that each intermediate curve is timelike. No...
Click to read more »Path space fibration
Kamis, 2025-07-10 06:16:19{\displaystyle \phi } is a homotopy equivalence; thus, the above decomposition says that any map is a fibration up to homotopy equivalence. If f {\displaystyle...
Click to read more »Stable ∞-category
Kamis, 2026-04-30 23:56:02in it is a fiber sequence if and only if it is a cofiber sequence. The homotopy category of a stable ∞-category is triangulated. A stable ∞-category admits...
Click to read more »George W. Whitehead
Selasa, 2026-04-14 19:26:44first to systematically calculate the homotopy groups of spheres. He is also central to the study of stable homotopy theory, in particular making concrete...
Click to read more »Shape theory (mathematics)
Senin, 2026-04-06 04:44:47topology that provides a more global view of the topological spaces than homotopy theory. The two coincide on compacta dominated homotopically by finite...
Click to read more »Eckmann–Hilton duality
Jumat, 2026-05-29 08:00:07In the mathematical disciplines of algebraic topology and homotopy theory, Eckmann–Hilton duality in its most basic form, consists of taking a given diagram...
Click to read more »Real projective space
Rabu, 2025-08-20 00:50:06quotient bundle. The higher homotopy groups of RPn are exactly the higher homotopy groups of Sn, via the long exact sequence on homotopy associated to a fibration...
Click to read more »Interior (topology)
Minggu, 2026-03-15 06:03:54Space compact connected Hausdorff metric uniform second-countable Homotopy homotopy group fundamental group Simplicial complex CW complex Polyhedral complex...
Click to read more »Contractible space
Sabtu, 2026-04-04 07:32:43homotopy type of a point. It follows that all the homotopy groups of a contractible space are trivial. Therefore any space with a nontrivial homotopy...
Click to read more »Mapping class group
Kamis, 2026-05-28 02:48:18deformation of the homeomorphisms themselves called homotopies. We define the mapping class group by taking homotopy classes of homeomorphisms, and inducing the...
Click to read more »Fibration of simplicial sets
Minggu, 2026-06-07 14:36:55In mathematics, especially in homotopy theory, a left fibration of simplicial sets is a map that has the right lifting property with respect to the horn...
Click to read more »General topology
Senin, 2026-04-27 00:10:45Space compact connected Hausdorff metric uniform second-countable Homotopy homotopy group fundamental group Simplicial complex CW complex Polyhedral complex...
Click to read more »List of algebraic topology topics
Kamis, 2026-01-15 18:27:40topological spaces up to homeomorphism, though usually most classify up to homotopy equivalence. Although algebraic topology primarily uses algebra to study...
Click to read more »Simple space
Jumat, 2024-03-08 08:45:11topological space that has a homotopy type of a CW complex and whose fundamental group is abelian and acts trivially on the homotopy and homology of the universal...
Click to read more »Goro Nishida
Kamis, 2026-05-14 21:54:18Japanese mathematician. He was a leading member of the Japanese school of homotopy theory, following in the tradition of Hiroshi Toda. Nishida received his...
Click to read more »Stiefel manifold
Jumat, 2026-03-06 14:54:46\mathbb {C} ^{n},} or H n ; {\displaystyle \mathbb {H} ^{n};} this is homotopy equivalent to the more restrictive definition, as the compact Stiefel manifold...
Click to read more »Nerve complex
Sabtu, 2026-05-23 00:09:51) {\displaystyle N(C)} is a 2-simplex (without its interior) and it is homotopy-equivalent to the original circle. A nerve theorem (or nerve lemma) is...
Click to read more »Collapse (topology)
Minggu, 2025-06-15 22:10:38collapse reduces a simplicial complex (or more generally, a CW complex) to a homotopy-equivalent subcomplex. Collapses, like CW complexes themselves, were invented...
Click to read more »Čech complex
Minggu, 2026-02-22 15:11:17ε-balls centered at points of X. By the nerve lemma, the Čech complex is homotopy equivalent to the union of the balls, also known as the offset filtration...
Click to read more »Jim Stasheff
Selasa, 2026-04-14 19:25:08physics. In the 1960s he wrote fundamental papers on higher homotopy theory and homotopy algebras. He introduced A ∞ {\displaystyle A_{\infty }} , Stasheff...
Click to read more »Unit interval
Kamis, 2025-04-24 18:59:02addition to its role in real analysis, the unit interval is used to study homotopy theory in the field of topology. In the literature, the term "unit interval"...
Click to read more »Novikov conjecture
Selasa, 2026-05-05 05:29:23originally posed the conjecture in 1965. The Novikov conjecture concerns the homotopy invariance of certain polynomials in the Pontryagin classes of a manifold...
Click to read more »Size homotopy group
Kamis, 2024-03-14 03:54:56The concept of size homotopy group is analogous in size theory of the classical concept of homotopy group. In order to give its definition, let us assume...
Click to read more »Profinite integer
Minggu, 2026-05-31 08:16:10This group is important because of its relation to Galois theory, étale homotopy theory, and the ring of adeles. In addition, it provides a basic tractable...
Click to read more »Lawvere's fixed-point theorem
Senin, 2026-02-09 22:08:17concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Initial topology
Sabtu, 2025-11-22 06:39:58set-theoretic continuum Pointless Algebraic combinatorial homology cohomology homotopy Differential Geometric low-dimensional knot Digital Key concepts Open set /...
Click to read more »N-group (category theory)
Minggu, 2026-04-05 21:07:24will have a homotopy n {\displaystyle n} -group at every point, which will encapsulate the Postnikov tower of the space up to the homotopy group π n {\displaystyle...
Click to read more »Generalised Whitehead product
Selasa, 2026-05-12 15:26:40certain restrictions). In homotopy theory, one assigns a group to each space X and positive integer p called the pth homotopy group of X. These groups...
Click to read more »Fields Medal
Kamis, 2026-05-14 21:36:19Nancy, France Collège de France, France "Achieved major results on the homotopy groups of spheres, especially in his use of the method of spectral sequences...
Click to read more »Deligne's conjecture on Hochschild cohomology
Minggu, 2026-05-10 04:42:00and Yan Soibelman, and others, after an initial input of construction of homotopy algebraic structures on the Hochschild complex. It is of importance in...
Click to read more »Nonabelian cohomology
Minggu, 2026-04-05 20:11:00the abelianization of homotopy (cf. Hurewicz theorem), then the nonabelian cohomology may be thought of as a dual of homotopy groups. See: Nonabelian...
Click to read more »Frank Adams
Kamis, 2026-04-23 18:13:58January 1989) was a British mathematician, one of the major contributors to homotopy theory. He was born in Woolwich, a suburb in south-east London, and attended...
Click to read more »Identity type
Jumat, 2026-04-24 23:01:36complex topic and has been the subject of research, such as the field of homotopy type theory. The identity type is one of 2 different notions of equality...
Click to read more »Triangulated category
Sabtu, 2026-04-25 04:36:35are the derived category of an abelian category, as well as the stable homotopy category. The exact triangles generalize the short exact sequences in an...
Click to read more »Lusternik–Schnirelmann category
Sabtu, 2026-04-25 04:36:20category, LS-category) of a topological space X {\displaystyle X} is the homotopy invariant defined to be the smallest integer number k {\displaystyle k}...
Click to read more »Line bundle
Senin, 2025-12-08 10:46:36invertible complex matrices, which have the homotopy type of a circle. From the perspective of homotopy theory, a real line bundle therefore behaves...
Click to read more »Topological modular forms
Minggu, 2026-03-15 09:03:02on the set tmf n ( X ) {\displaystyle \operatorname {tmf} ^{n}(X)} of homotopy classes of continuous maps from X to tmf n {\displaystyle \operatorname...
Click to read more »Equivariant cohomology
Jumat, 2026-04-17 04:06:38{\displaystyle EG\times _{G}X} is known as the Borel construction, or homotopy quotient. Projection onto the first factor gives it the structure of a...
Click to read more »Aldridge Bousfield
Rabu, 2026-04-01 03:24:30Society "for contributions to homotopy theory and for exposition". Bousfield, Aldridge K.; Kan, Daniel M. (1972), Homotopy Limits, Completions and Localizations...
Click to read more »Absolute neighborhood retract
Senin, 2026-06-01 02:59:49ANR) is a "nice"[weasel words] topological space that is considered in homotopy theory; more specifically, in the theory of retracts.[jargon] For a more...
Click to read more »Pro-simplicial set
Minggu, 2020-04-12 23:09:16sets has finite homotopy groups. Pro-simplicial sets show up in shape theory, in the study of localization and completion in homotopy theory, and in the...
Click to read more »Topological group
Senin, 2026-05-18 01:09:04isomorphic in the homotopy category to the loop space of B G {\displaystyle BG} ; that implies various restrictions on the homotopy type of G. Some of...
Click to read more »Bloch's higher Chow group
Senin, 2026-06-01 07:20:11Chow groups. One of the motivations for higher Chow groups comes from homotopy theory. In particular, if α , β ∈ Z ∗ ( X ) {\displaystyle \alpha ,\beta...
Click to read more »Agnès Beaudry
Minggu, 2025-12-28 22:29:43specializing in algebraic topology, including stable homotopy theory, chromatic homotopy theory, equivariant homotopy theory, and applications of these theories...
Click to read more »Connective spectrum
Rabu, 2024-03-27 01:29:53topology, a branch of mathematics, a connective spectrum is a spectrum whose homotopy sets π k {\displaystyle \pi _{k}} of negative degrees are zero. Kuku, Aderemi...
Click to read more »List of general topology topics
Senin, 2026-01-05 03:44:02covering Simply connected Semi-locally simply connected Path (topology) Homotopy Homotopy lifting property Pointed space Wedge sum Smash product Cone (topology)...
Click to read more »Almgren's isomorphism theorem
Kamis, 2026-05-14 21:34:37homotopy equivalent to the infinite real projective space. Let M be a Riemannian manifold. Almgren isomorphism theorem asserts that the m-th homotopy...
Click to read more »Sze-Tsen Hu
Sabtu, 2024-06-15 11:12:16known as Steve Hu, was a Chinese-American mathematician, specializing in homotopy theory. Hu received his B.S. from the National Central University in Nanking...
Click to read more »Inclusion map
Selasa, 2026-04-07 07:06:21} the inclusion map yields an isomorphism between all homotopy groups (that is, it is a homotopy equivalence). Inclusion maps in geometry come in different...
Click to read more »Inductive type
Minggu, 2026-03-15 16:29:25type theories with the univalence axiom, this correspondence holds up to homotopy (propositional equality). M-types are dual to W-types, and represent coinductive...
Click to read more »Tensor–hom adjunction
Rabu, 2026-03-25 15:14:30duality Change of rings May, J.P.; Sigurdsson, J. (2006). Parametrized Homotopy Theory. A.M.S. p. 253. ISBN 0-8218-3922-5. Bourbaki, Nicolas (1989), Elements...
Click to read more »Boundary (topology)
Sabtu, 2026-01-03 21:29:34Space compact connected Hausdorff metric uniform second-countable Homotopy homotopy group fundamental group Simplicial complex CW complex Polyhedral complex...
Click to read more ȃtale fundamental group
Kamis, 2026-05-14 21:34:51topological space ( X , x ) {\displaystyle (X,x)} is defined as the group of homotopy classes of loops based at x {\displaystyle x} . This definition works well...
Click to read more »Monodromy theorem
Jumat, 2025-10-31 04:30:49Homotopy with fixed endopoints is necessary for the monodromy theorem to hold....
Click to read more »Floer homology
Kamis, 2026-05-28 19:13:01induces a filtration on the chain complex of each theory, whose chain homotopy type is a knot invariant. (Their homologies satisfy similar formal properties...
Click to read more »Operad
Jumat, 2026-05-08 21:36:40and Mikhail Kapranov discovered that some duality phenomena in rational homotopy theory could be explained using Koszul duality of operads. Operads have...
Click to read more »Quasigroup
Selasa, 2025-11-18 10:07:07Q. A quasigroup homomorphism is just a homotopy for which the three maps are equal. An isotopy is a homotopy for which each of the three maps (α, β,...
Click to read more »Dold–Kan correspondence
Jumat, 2026-01-23 09:58:59{\displaystyle n} th homotopy group of the corresponding simplicial abelian group, and a chain homotopy corresponds to a simplicial homotopy. (In fact, the...
Click to read more »Cubical type theory
Kamis, 2026-04-30 17:12:23a computational interpretation to univalent foundations (also known as homotopy type theory). In cubical type theory, function extensionality and univalence...
Click to read more »Eilenberg–Steenrod axioms
Sabtu, 2026-05-09 06:27:011 ( A , ∅ ) {\displaystyle H_{i-1}(A,\varnothing )} ). The axioms are: Homotopy: Homotopic maps induce the same map in homology. That is, if g : ( X ,...
Click to read more »Joyal's extension and lifting theorems
Kamis, 2026-05-14 21:59:38In mathematics, Joyal's theorem is a theorem in homotopy theory that provides necessary and sufficient conditions for the solvability of a certain lifting...
Click to read more »Category of elements
Minggu, 2026-05-10 08:20:28category of elements of a simplicial set is fundamental in simplicial homotopy theory, a branch of algebraic topology. More generally, the category of...
Click to read more »Klein bottle
Minggu, 2026-06-07 07:06:132π. Regular 3D immersions of the Klein bottle fall into three regular homotopy classes. The three are represented by: the "traditional" Klein bottle;...
Click to read more »Ronald Brown (mathematician)
Jumat, 2026-03-20 11:56:27Categories and Homology, Homotopy and Applications, which he helped found. Since 2006, he has been involved with Journal of Homotopy and Related Structures...
Click to read more »Adjoint functors
Minggu, 2026-04-19 00:30:14space [SX, Y] of homotopy classes of maps from the suspension SX of X to Y is naturally isomorphic to the space [X, ΩY] of homotopy classes of maps from...
Click to read more »Nielsen–Schreier theorem
Jumat, 2026-04-24 20:33:58the original loop-edges a,b. Contracting one of the edges of Y gives a homotopy equivalence to a bouquet of three circles, so that H = π1(Y) is a free...
Click to read more »Poincaré lemma
Minggu, 2026-05-10 23:34:53special case of the homotopy invariance of de Rham cohomology; in fact, it is common to establish the lemma by showing the homotopy invariance or at least...
Click to read more »Analytic torsion
Sabtu, 2026-06-06 03:41:16algebraic topology that could distinguish between closed manifolds which are homotopy equivalent but not homeomorphic, and can thus be seen as the birth of geometric...
Click to read more »Projective orthogonal group
Jumat, 2025-10-17 15:05:55Homotopy groups above π 1 {\displaystyle \pi _{1}} do not change under covers, so they agree with those of the orthogonal group. The lower homotopy groups...
Click to read more »Donald M. Davis (mathematician)
Selasa, 2026-03-03 12:56:37Mathematical Society. Since 2002, he has been Executive Editor of Homology, Homotopy and Applications. Davis has published in algebraic topology, differential...
Click to read more »Applied category theory
Selasa, 2026-01-27 10:56:30concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »KK-theory
Selasa, 2026-04-28 20:24:34unitary operator from the 0-end of the homotopy to the first cycle, and a unitary operator from the 1-end of the homotopy to the second cycle. The KK-group...
Click to read more »Segal's conjecture
Minggu, 2025-07-27 23:34:58ring conjecture, or, more briefly, the Segal conjecture, is a theorem in homotopy theory, a branch of mathematics. The theorem relates the Burnside ring...
Click to read more »Derived tensor product
Minggu, 2026-03-15 13:16:42the categories of right A-modules and left A-modules and D refers to the homotopy category (i.e., derived category). By definition, it is the left derived...
Click to read more »Quasi-isomorphism
Kamis, 2026-04-16 00:36:57homology-local theory, in the sense of Bousfield localization in homotopy theory. Chain homotopy equivalence Derived category Gelfand, Sergei I., Manin, Yuri...
Click to read more »Yoneda lemma
Jumat, 2026-05-08 18:40:40concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Steve Awodey
Rabu, 2026-04-15 18:46:40philosophy of mathematics. He is one of the originators of the field of homotopy type theory. He was a member of the School of Mathematics at the Institute...
Click to read more »Denis-Charles Cisinski
Selasa, 2025-09-16 00:18:26March 10, 1976) is a mathematician focussing on higher category theory, homotopy theory, K-theory and algebraic geometry. In 2001, Cisinski model structures...
Click to read more »Steenrod algebra
Sabtu, 2026-04-25 22:32:27{\displaystyle X} , such that this action behaves well with respect to the stable homotopy category, i.e., there is an isomorphism E ∗ ( E ) ⊗ π ∗ ( E ) E ∗ ( X )...
Click to read more »Indistinguishable particles
Sabtu, 2026-03-21 06:26:31where d ≥ 3, then this homotopy class only has one element. If M is R 2 {\displaystyle \mathbb {R} ^{2}} , then this homotopy class has countably many...
Click to read more »Eilenberg–Zilber theorem
Minggu, 2026-05-10 19:57:39C^{*}(X\times Y)} which are also homotopy equivalences, as witnessed by the duals of the preceding equations, using the dual homotopy H ∗ {\displaystyle H^{*}}...
Click to read more »Simplicial presheaf
Senin, 2026-01-26 03:41:31In mathematics, more specifically in homotopy theory, a simplicial presheaf is a presheaf on a site (e.g., the category of topological spaces) taking values...
Click to read more »Center (category theory)
Minggu, 2026-04-05 20:28:14concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Serre spectral sequence
Jumat, 2025-11-07 01:11:55usual cohomology. For a path connected base, all the different fibers are homotopy equivalent. In particular, their cohomology is isomorphic, so the choice...
Click to read more »Set theory
Kamis, 2026-05-28 22:09:36univalent foundations and related to it homotopy type theory. Within homotopy type theory, a set may be regarded as a homotopy 0-type, with universal properties...
Click to read more »Assembly map
Rabu, 2025-09-03 18:43:19geometric topology. From the homotopy-theoretical viewpoint, an assembly map is a universal approximation of a homotopy invariant functor by a homology...
Click to read more »May spectral sequence
Jumat, 2026-02-27 04:02:08Adams spectral sequence, which is in turn used for calculating the stable homotopy groups of spheres. The May spectral sequence is described in detail in...
Click to read more »Vertical bar
Selasa, 2026-03-17 15:37:15truncation (a type former that truncates a type down to a mere proposition in homotopy type theory): for any a : A {\displaystyle a:A} (read "term a {\displaystyle...
Click to read more »Operad algebra
Rabu, 2026-04-15 22:39:41is a homotopy equivalence, then the ∞-category of algebras over O in C is equivalent to the ∞-category of algebras over O' in C. En-ring Homotopy Lie algebra...
Click to read more »Weak equivalence between simplicial sets
Senin, 2025-09-29 11:53:41an equivalence of categories for each ∞-category V, where ho means the homotopy category of an ∞-category, f ∗ : Hom _ ( Y , V ) ≃ → Hom _ ( X , V ) ≃...
Click to read more »Spectral sequence
Senin, 2026-04-27 05:27:42converging to stable homotopy groups of spheres Federer spectral sequence converging to homotopy groups of a function space. Homotopy fixed point spectral...
Click to read more »Signature operator
Rabu, 2025-11-05 15:42:24and Miller proved that the higher indices of the signature operator are homotopy-invariant. Hirzebruch signature theorem Pontryagin class Friedrich Hirzebruch...
Click to read more »Monodromy
Selasa, 2026-04-28 20:22:13fundamental group π 1 ( X , x ) {\displaystyle \pi _{1}(X,x)} , the covering homotopy property shows they define the same action γ ⋅ x ~ = γ ′ ⋅ x ~ {\displaystyle...
Click to read more »8
Selasa, 2026-05-26 10:32:50The Bott periodicity theorem describes the eightfold periodicity of the homotopy groups of the direct limit of the orthogonal groups O(n). This has many...
Click to read more »Joyal model structure
Kamis, 2026-04-09 11:59:57are all ∞-categories and it furthermore models the homotopy theory of CW complexes up to homotopy equivalence, with the correspondence between simplicial...
Click to read more »System of polynomial equations
Minggu, 2026-05-17 11:46:28point which is close to a solution. Therefore, it is a basic tool for the homotopy continuation method described below. Optimization is rarely used for solving...
Click to read more »Ravenel's conjectures
Selasa, 2025-03-25 00:29:08conjectures are a set of mathematical conjectures in the field of stable homotopy theory posed by Douglas Ravenel at the end of a paper published in 1984...
Click to read more »Solid torus
Selasa, 2026-05-12 00:17:49disk D 2 {\displaystyle D^{2}} is contractible, the solid torus has the homotopy type of a circle, S 1 {\displaystyle S^{1}} . Therefore the fundamental...
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Senin, 2026-04-20 06:36:14space K(G, 1), its homotopy equivalences, up to homotopy, can be identified with automorphisms of the fundamental group); all homotopy equivalences of the...
Click to read more »Isomorphism
Selasa, 2026-05-12 22:53:41but must be distinguished to consider their intersection, sum, etc. In homotopy theory, the fundamental group of a space X {\displaystyle X} at a point...
Click to read more »Michael Boardman
Minggu, 2026-03-08 02:05:49known for his construction of the first rigorously correct model of the homotopy category of spectra. He received his PhD from the University of Cambridge...
Click to read more »Whitehead product
Kamis, 2025-11-27 01:12:10the Whitehead product is a graded quasi-Lie algebra structure on the homotopy groups of a space. It was defined by J. H. C. Whitehead in (Whitehead 1941)...
Click to read more »Crystallographic defect
Kamis, 2025-10-02 05:07:09point defects, line defects, planar defects, bulk defects. Topological homotopy establishes a mathematical method of characterization. Point defects are...
Click to read more »Homotopy group with coefficients
Kamis, 2023-12-21 02:20:17{\displaystyle i\geq 2} , the i-th homotopy group with coefficients in an abelian group G of a based space X is the pointed set of homotopy classes of based maps from...
Click to read more »Hypercovering
Kamis, 2026-05-14 21:32:46In mathematics, and in particular homotopy theory, a hypercovering (or hypercover) is a simplicial object that generalises the Čech nerve of a cover. For...
Click to read more »Pre-abelian category
Selasa, 2024-03-26 10:45:06concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Polynomial functor (type theory)
Selasa, 2026-04-07 07:19:14"Inductive types in homotopy type theory". arXiv:1201.3898 [math.LO]. Awodey, Steve; Gambino, Nicola; Sojakova, Kristina (2015-04-21). "Homotopy-initial algebras...
Click to read more »Cohomotopy set
Selasa, 2024-12-17 14:59:26continuous maps to the category of sets and functions. They are dual to the homotopy groups, but less studied. The p-th cohomotopy set of a pointed topological...
Click to read more »G-spectrum
Rabu, 2024-03-27 01:29:52with an action of a finite group G. The important notion is that of the homotopy fixed point set X h G {\displaystyle X^{hG}} . There is always X G → X...
Click to read more »Pushforward (homology)
Rabu, 2025-08-20 00:35:37functoriality of the pushforward.) A main result about the push-forward is the homotopy invariance: if two maps f , g : X → Y {\displaystyle f,g\colon X\rightarrow...
Click to read more »Stable normal bundle
Minggu, 2023-12-03 01:37:33notably PL-manifolds and topological manifolds. There is also an analogue in homotopy theory for Poincaré spaces, the Spivak spherical fibration, named after...
Click to read more »Nilpotence theorem
Minggu, 2026-04-05 20:11:59topology, the nilpotence theorem gives a condition for an element in the homotopy groups of a ring spectrum to be nilpotent, in terms of the complex cobordism...
Click to read more »Natural numbers object
Rabu, 2026-04-22 06:33:02concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Ismar Volić
Kamis, 2026-03-26 16:28:44configuration space integrals, finite type invariants, Milnor invariants, rational homotopy theory, topological data analysis, and social choice theory. Volić's book...
Click to read more »Suspension (topology)
Rabu, 2025-08-20 03:04:27where S 0 {\displaystyle S^{0}} is a discrete space with two points. 5. In Homotopy type theory, S X {\displaystyle SX} be defined as a higher inductive type...
Click to read more »Maslov index
Minggu, 2026-04-26 10:45:20{\displaystyle \mathbf {Z} } . The Maslov index may be viewed as the corresponding homotopy invariant, assigning an integer to a loop in the Lagrangian Grassmannian...
Click to read more »Nilpotent space
Sabtu, 2026-01-03 05:28:01nilpotent group; π {\displaystyle \pi } acts nilpotently on the higher homotopy groups π i ( X ) , i ≥ 2 {\displaystyle \pi _{i}(X),i\geq 2} , i.e., there...
Click to read more »Robert Wayne Thomason
Selasa, 2026-04-14 19:25:50Institute of Technology University of Chicago Johns Hopkins University Thesis Homotopy Colimits in Cat(+ Category of Small Categories) with Applications to Algebraic...
Click to read more »Coherence
Kamis, 2026-03-12 17:17:55various compositions of elementary morphisms are equal Coherency (homotopy theory) in homotopy theory and (higher) category theory Coherent sampling, a relationship...
Click to read more »Cyclomatic complexity
Selasa, 2026-06-02 20:32:40{G}})=\operatorname {rank} H_{1}({\tilde {G}}).} It can also be computed via homotopy. If a (connected) control-flow graph is considered a one-dimensional CW...
Click to read more »Geometric topology
Minggu, 2026-05-17 01:33:56required distinguishing spaces that are homotopy equivalent but not homeomorphic. This was the origin of simple homotopy theory. The use of the term geometric...
Click to read more »Wall's finiteness obstruction
Rabu, 2021-01-20 04:55:08within mathematics, the obstruction to a finitely dominated space X being homotopy-equivalent to a finite CW-complex is its Wall finiteness obstruction w(X)...
Click to read more »Kathryn Hess
Rabu, 2026-04-01 03:31:48Polytechnique Fédérale de Lausanne (EPFL) since 1999. She is known for her work on homotopy theory, category theory, and algebraic topology, both pure and applied...
Click to read more »Groupoid
Minggu, 2026-05-17 11:37:49In mathematics, especially in category theory and homotopy theory, a groupoid (less often Brandt groupoid or virtual group) generalises the notion of group...
Click to read more »Spin group
Minggu, 2026-05-17 07:35:44(killing) homotopy groups of increasing order. This is done by constructing short exact sequences starting with an Eilenberg–MacLane space for the homotopy group...
Click to read more »Initial and terminal objects
Sabtu, 2026-04-25 04:36:24concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Lam Siu-por
Selasa, 2026-05-26 09:23:36far, published when he was completing his PhD. "On ex-homotopy theory and generalized homotopy products". The University of Hong Kong. 1978. Archived...
Click to read more »List object
Selasa, 2026-04-07 07:38:45concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Abstract algebra
Minggu, 2026-05-03 04:18:45Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
Click to read more »Mikhail Kapranov
Sabtu, 2025-09-06 14:58:40Kapranov published “ ∞ {\displaystyle \infty } -Groupoids as a Model for a Homotopy Category”, in which they claimed to provide a rigorous mathematical formulation...
Click to read more »Timeline of category theory and related mathematics
Sabtu, 2026-05-30 10:19:08ISSN 0271-4132. LCCN 96-37049. MR 1436913. Retrieved 2021-12-08. George Whitehead; Fifty years of homotopy theory Haynes Miller; The origin of sheaf theory...
Click to read more »Pullback (category theory)
Jumat, 2026-05-01 20:21:01concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Sullivan conjecture
Selasa, 2026-03-17 00:14:16spaces can refer to any of several results and conjectures prompted by homotopy theory work of Dennis Sullivan. A basic theme and motivation concerns the...
Click to read more »Rick Jardine
Minggu, 2026-02-08 09:23:24Belleville, Canada) is a Canadian mathematician working in the fields of homotopy theory, category theory, and number theory. Jardine obtained his Ph.D....
Click to read more »Computational topology
Selasa, 2025-12-09 16:40:29for homotopy groups of spheres. Computational methods for solving systems of polynomial equations. Brown has an algorithm to compute the homotopy groups...
Click to read more »Liao Shijun
Jumat, 2025-09-26 12:47:071963) is a fluid mechanics and applied mathematics expert working in homotopy analysis method (HAM), nonlinear waves, nonlinear dynamics, and applied...
Click to read more »Projective unitary group
Selasa, 2026-06-02 22:46:51_{n+1}(BX)} between the homotopy groups of a space X and the homotopy groups of its classifying space BX, combined with the homotopy type of the circle U(1)...
Click to read more »Hilbert manifold
Senin, 2025-07-21 11:10:33theorem: If X {\displaystyle X} is a compact topological space or has the homotopy type of a CW complex then every (real or complex) Hilbert space bundle...
Click to read more »Monomorphism
Senin, 2026-05-04 14:44:59concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Mapping cylinder
Jumat, 2026-03-20 12:19:46M_{f}} together with a homotopy equivalence between them. The construction serves to replace any map of topological spaces by a homotopy equivalent cofibration...
Click to read more »Category (mathematics)
Sabtu, 2026-06-06 13:45:30groupoid of X {\displaystyle X} ): two loops (under equivalence relation of homotopy) may not have the same base point so they cannot be multiplied with each...
Click to read more »Conservative functor
Selasa, 2024-03-05 14:41:07concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Handlebody
Minggu, 2025-12-07 07:45:38the study of manifolds as simplicial complexes and CW complexes play in homotopy theory, allowing one to analyze a space in terms of individual pieces and...
Click to read more »Julie Bergner
Kamis, 2026-03-05 11:58:34Elizabeth Bergner is a mathematician specializing in algebraic topology, homotopy theory, and higher category theory. She is a professor of mathematics at...
Click to read more »Currying
Selasa, 2026-04-07 07:05:24object. In the theory of function spaces, such as in functional analysis or homotopy theory, one is commonly interested in continuous functions between topological...
Click to read more »Stephen Smale
Rabu, 2026-05-06 07:37:41oriented diffeomorphism group of the two-dimensional sphere has the same homotopy type as the special orthogonal group of 3 × 3 matrices. Smale's theorem...
Click to read more »Quillen adjunction
Selasa, 2025-10-14 23:30:09In homotopy theory, a branch of mathematics, a Quillen adjunction between two closed model categories C and D is a special kind of adjunction between categories...
Click to read more »Witt group
Kamis, 2026-05-14 21:35:43perfect field is isomorphic to the motivic stable homotopy group of spheres π0,0(S0,0) (see "A¹ homotopy theory"). Two fields are said to be Witt equivalent...
Click to read more »Topological insulator
Rabu, 2026-05-27 09:05:10is called the n-th homotopy group of M {\displaystyle M} , noted π n ( M ) {\displaystyle \pi _{n}(M)} . The relevant homotopy groups for two-band systems...
Click to read more »Tetracategory
Jumat, 2026-02-27 13:39:40concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Witold Hurewicz
Senin, 2026-04-06 16:44:43higher homotopy groups in 1935–36, his discovery of the long exact homotopy sequence for fibrations in 1941, and the Hurewicz theorem connecting homotopy and...
Click to read more »Gunnar Carlsson
Rabu, 2026-03-04 12:58:19"for contributions to algebraic topology, particularly equivariant stable homotopy theory, algebraic K-theory, and applied algebraic topology". In 2008, Carlsson...
Click to read more »Synthetic mathematics
Minggu, 2026-05-17 00:40:50employed to ease the formalization of mathematics. Homotopy type theory is a synthetic approach to homotopy theory using the language of univalent foundations...
Click to read more »61 (number)
Selasa, 2026-05-26 02:39:05Guozhen; Xu, Zhouli (2017). "The triviality of the 61-stem in the stable homotopy groups of spheres". Annals of Mathematics. 186 (2): 501–580. arXiv:1601...
Click to read more »Diagonal functor
Selasa, 2026-04-07 07:21:15concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Limit (category theory)
Jumat, 2026-05-29 08:01:37concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Fabien Morel
Senin, 2025-11-17 03:46:5822 January 1965) is a French algebraic geometer and key developer of A¹ homotopy theory with Vladimir Voevodsky. Among his accomplishments is the proof...
Click to read more »Rational homology sphere
Rabu, 2025-08-20 00:48:22(for which a weak homotopy equivalence from the circle exists) is a rational homotopy 1 {\displaystyle 1} -sphere, which is not a homotopy 1 {\displaystyle...
Click to read more »Essentially surjective functor
Selasa, 2024-03-05 02:02:20concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Join (topology)
Rabu, 2026-03-25 21:28:44{\displaystyle A'} are homotopy equivalent, then A ⋆ B {\displaystyle A\star B} and A ′ ⋆ B {\displaystyle A'\star B} are homotopy equivalent too. Given...
Click to read more »Coequalizer
Selasa, 2026-05-05 22:44:36concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »∞-topos
Minggu, 2026-04-05 20:11:46groupoid object in X is effective. Mathematics portal Bousfield localization Homotopy hypothesis – Hypothesis in mathematical category theory ∞-groupoid – Abstract...
Click to read more »David Corfield
Senin, 2026-04-27 01:01:20571–579. Bibcode:2011SHPSA..42..571C. doi:10.1016/j.shpsa.2011.09.013. Modal Homotopy Type Theory: The Prospect of a New Logic for Philosophy, Oxford University...
Click to read more »J. Peter May
Selasa, 2026-03-24 15:54:41mathematician working in the fields of algebraic topology, category theory, homotopy theory, and the foundational aspects of spectra. He is known, in particular...
Click to read more »Universal property
Senin, 2026-04-06 17:01:24concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Projective linear group
Jumat, 2026-05-22 20:03:21fiber is C× ≅ S1, so up to homotopy, GL → PGL is a circle bundle. The higher homotopy groups of the circle vanish, so the homotopy groups of GL(n, C) and...
Click to read more »Braid group
Kamis, 2026-05-21 08:25:36informal discussion of braid groups on firm ground, one needs to use the homotopy concept of algebraic topology, defining braid groups as fundamental groups...
Click to read more »Zero morphism
Kamis, 2026-02-19 12:31:39concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Embarrassingly parallel
Senin, 2026-02-16 22:14:37be embarrassing not to develop parallel implementations of polynomial homotopy continuation methods." The term is first found in the literature in a 1986...
Click to read more »Differential graded Lie algebra
Jumat, 2022-03-04 05:27:14compatible. Such objects have applications in deformation theory and rational homotopy theory. A differential graded Lie algebra is a graded vector space L =...
Click to read more »Bousfield localization
Rabu, 2026-03-18 19:51:03local sphere S ( p ) {\displaystyle S_{(p)}} . The stable homotopy category is the homotopy category (in the sense of model categories) of spectra, endowed...
Click to read more »Nonabelian algebraic topology
Rabu, 2026-02-18 07:17:15Algebraic Topology (NAAT) "can be applied to determine homotopy invariants of spaces, and homotopy classification of maps, in cases which include some classical...
Click to read more »Isomorphism of categories
Kamis, 2026-02-19 12:17:43concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Nielsen theory
Minggu, 2025-12-14 23:07:59{\mathit {MF}}[f]=\min\{\#\mathrm {Fix} (g)\,|\,g\sim f\},} where ~ indicates homotopy of mappings, and #Fix(g) indicates the number of fixed points of g. The...
Click to read more »Out(Fn)
Minggu, 2026-05-10 12:32:11\mathbb {R} } -graph X homotopy equivalent to a bouquet of n circles together with a certain choice of a free homotopy class of a homotopy equivalence from...
Click to read more »Total curvature
Rabu, 2026-02-25 01:02:55invariant under a regular homotopy of a curve: it is the degree of the Gauss map. However, it is not invariant under homotopy: passing through a kink (cusp)...
Click to read more »Annals of Mathematics Studies
Selasa, 2026-06-02 05:52:11R. C. Gunning 1962-03-01 96 978-0691079950 49 Composition Methods in Homotopy Groups of Spheres. Hirosi Toda 1963 193 9780691095868 50 Cohomology Operations:...
Click to read more »End (category theory)
Senin, 2026-04-06 16:46:27concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »List of cohomology theories
Minggu, 2026-03-15 09:05:06{\displaystyle X} to the spectrum Y {\displaystyle Y} , given (roughly) as homotopy classes of maps. [ X , Y ] n = [ S n X , Y ] {\displaystyle [X,Y]_{n}=[S^{n}X...
Click to read more »Stable model category
Selasa, 2017-06-20 20:09:48an equivalence of the homotopy category with itself. The prototypical examples are the category of spectra in the stable homotopy theory and the category...
Click to read more »Cohomology operation
Senin, 2025-07-07 02:58:07cohomology operation concept became central to algebraic topology, particularly homotopy theory, from the 1950s onwards, in the shape of the simple definition that...
Click to read more »Full and faithful functors
Jumat, 2025-09-19 12:34:55objects are given by a space only up to homotopy. Since the notion of injection and surjection are not homotopy invariant notions (consider an interval...
Click to read more »Ralph Louis Cohen
Minggu, 2026-02-01 04:11:03supervision of Edgar H. Brown, Jr. His thesis was titled On Odd Primary Stable Homotopy Theory and was published in the Memoirs of the American Mathematical Society...
Click to read more »Quaternionic projective space
Selasa, 2023-06-06 00:30:42space. It also follows from rational homotopy theory that H P n {\displaystyle \mathbb {HP} ^{n}} has infinite homotopy groups only in dimensions 4 and 4...
Click to read more »Higher Topos Theory
Jumat, 2025-12-26 16:42:24Topos Theory (along with new material) to Kerodon, an "online resource for homotopy-coherent mathematics" inspired by the Stacks Project. Higher Topos Theory...
Click to read more »Point-surjective morphism
Jumat, 2025-06-06 02:11:55concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Simplicial approximation theorem
Senin, 2026-05-25 23:22:27There is a further simplicial approximation theorem for homotopies, stating that a homotopy between continuous mappings can likewise be approximated...
Click to read more »Toda bracket
Jumat, 2025-06-20 07:32:22homotopy classes of maps, in particular on homotopy groups of spheres, named after Hiroshi Toda, who defined them and used them to compute homotopy groups...
Click to read more »John Rognes (mathematician)
Sabtu, 2026-05-09 07:09:37Rognes at the workshop Modern foundations for stable homotopy theory, Oberwolfach 2005...
Click to read more »Barratt–Priddy theorem
Selasa, 2025-07-08 15:54:35In homotopy theory, a branch of mathematics, the Barratt–Priddy theorem (also referred to as Barratt–Priddy–Quillen theorem) expresses a connection between...
Click to read more »3-sphere
Selasa, 2026-04-28 10:00:27to the 3-sphere. As to the homotopy groups, we have π1(S3) = π2(S3) = 0 and π3(S3) is infinite cyclic. The higher-homotopy groups (k ≥ 4) are all finite...
Click to read more »Conley index theory
Minggu, 2026-05-17 07:35:36{\displaystyle S} . The Conley index h ( S ) {\displaystyle h(S)} is the homotopy type of a space built from a certain pair ( N 1 , N 2 ) {\displaystyle...
Click to read more »Redshift conjecture
Selasa, 2026-04-14 12:52:04In mathematics, more specifically in chromatic homotopy theory, the redshift conjecture states, roughly, that algebraic K-theory K ( R ) {\displaystyle...
Click to read more »Milnor map
Sabtu, 2025-07-19 10:07:00parallelizable manifoldspg 75. Milnor fibers are special because they have the homotopy type of a bouquet of spherespg 78. The number of these spheres is the Milnor...
Click to read more »3-manifold
Kamis, 2026-04-16 02:34:49{\text{Hom}}(\pi ,\mathbb {Z} )\end{aligned}}} From this information a basic homotopy theoretic classification of 3-manifolds can be found. Note from the Postnikov...
Click to read more »E∞-operad
Jumat, 2026-03-20 11:59:00to all higher homotopies". (An operad that describes a multiplication that is associative but not necessarily commutative "up to homotopy" is called an...
Click to read more »Cokernel
Rabu, 2025-06-11 12:24:15concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Duffing equation
Selasa, 2025-07-08 03:45:51methods such as Euler's method and Runge–Kutta methods can be used. The homotopy analysis method (HAM) has also been reported for obtaining approximate...
Click to read more »Thomas Streicher
Kamis, 2025-04-24 04:01:32work other models with non-trivial identity types were studied, including homotopy type theory which has been proposed as a foundation for mathematics in...
Click to read more »Stephen Halperin
Jumat, 2025-12-12 08:50:16Nice, and in 1995 at the University of Lille. His research deals with homotopy theory and homology of loop spaces with applications in geometry. He wrote...
Click to read more »Joseph Neisendorfer
Minggu, 2024-04-07 16:58:4622, 1945 in Chicago) is an American mathematician known for his work in homotopy theory, an area of algebraic topology. He is a Fellow of the American Mathematical...
Click to read more »Paul Balmer
Minggu, 2026-03-08 07:06:55triangular geometry, algebraic geometry, modular representation theory, and homotopy theory. He is a professor of mathematics at the University of California...
Click to read more »P-compact group
Rabu, 2026-03-25 20:41:17group is the rank of its maximal torus. The p-completion, in the sense of homotopy theory, of (the classifying space of) a compact connected Lie group defines...
Click to read more »John Coleman Moore
Kamis, 2025-02-27 13:59:08Society. He died in 2016 at the age of 92. Moore, John C. (May 1954). "On Homotopy Groups of Spaces with a Single Non-Vanishing Homology Group". Annals of...
Click to read more »Lean (proof assistant)
Rabu, 2026-05-27 06:22:281 and 2, were experimental and contained features such as support for homotopy type theory-based foundations that were later dropped. Lean 3 (first released...
Click to read more »Anyon
Senin, 2026-05-25 20:29:52higher-dimensional representations of the permutation group. The fact that the homotopy classes of paths (i.e. notion of equivalence on braids) are relevant hints...
Click to read more »Jouanolou's trick
Sabtu, 2026-05-09 06:31:57space fibers from an affine variety W to X. Moreover, the variety W is homotopy-equivalent to X, and W has the technically advantageous property of being...
Click to read more »Polynomial differential form
Minggu, 2025-09-07 03:57:37Theory and Rational Homotopy Type, Memoirs of the A. M. S., vol. 179, 1976. Hinich, Vladimir (1997-02-11). "Homological algebra of homotopy algebras". arXiv:q-alg/9702015...
Click to read more »Refinement (category theory)
Jumat, 2026-03-27 03:58:54concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Motive (algebraic geometry)
Senin, 2026-06-01 16:09:59varieties f : X → Y {\displaystyle f:X\to Y} . From here we can form the homotopy category K b ( S m C o r ) {\displaystyle K^{b}({\mathcal {SmCor}})} of...
Click to read more »Sphere bundle
Selasa, 2022-06-28 23:47:12generalization of the concept of a sphere bundle, is a fibration whose fibers are homotopy equivalent to spheres. For example, the fibration BTop ( R n ) → BTop...
Click to read more »Institute for Advanced Study
Selasa, 2026-05-19 12:16:36Langlands and the Langlands program. The IAS is a main center of research for homotopy type theory, a modern approach to the foundations of mathematics which...
Click to read more »Simply connected space
Minggu, 2026-05-17 11:05:46{\displaystyle q} while keeping both endpoints fixed. Explicitly, there exists a homotopy F : [ 0 , 1 ] × [ 0 , 1 ] → X {\displaystyle F:[0,1]\times [0,1]\to X}...
Click to read more »Commutative diagram
Kamis, 2026-01-29 13:50:31concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Lift (mathematics)
Jumat, 2026-02-20 04:43:44Lifts are ubiquitous; for example, the definition of fibrations (see Homotopy lifting property) and the valuative criteria of separated and proper maps...
Click to read more »Free category
Senin, 2026-04-06 16:46:10concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Conjecture
Sabtu, 2026-05-09 05:00:11coarser form of equivalence than homeomorphism called homotopy equivalence: if a 3-manifold is homotopy equivalent to the 3-sphere, then it is necessarily...
Click to read more »Acyclic model
Minggu, 2025-11-09 08:08:04homotopy between f {\displaystyle f} and g {\displaystyle g} . In particular the chain map f {\displaystyle f} is unique up to natural chain homotopy...
Click to read more »Hopf–Whitney theorem
Rabu, 2025-05-28 03:43:12mathematics, especially algebraic topology and homotopy theory, the Hopf–Whitney theorem is a result relating the homotopy classes between a CW complex and a multiply...
Click to read more »Mayer–Vietoris sequence
Rabu, 2026-04-22 21:38:34homology of dimension one. Similar to the fundamental group or the higher homotopy groups of a space, homology groups are important topological invariants...
Click to read more »Forgetful functor
Senin, 2026-04-06 16:39:25concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Cartesian closed category
Rabu, 2026-05-20 16:03:50concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Künneth theorem
Kamis, 2025-07-10 03:31:05homotopical theory of modules over highly structured ring spectra. The homotopy category of such modules closely resembles the derived category in homological...
Click to read more »Frederick J. Almgren Jr.
Senin, 2024-11-25 09:44:54Geometric measure theory Institutions Princeton University Thesis The Homotopy Groups of the Integral Cycle Groups (1962) Doctoral advisor Herbert Federer...
Click to read more »Nisnevich topology
Kamis, 2026-05-14 21:59:47the category of schemes which has been used in algebraic K-theory, A¹ homotopy theory, and the theory of motives. It was originally introduced by Yevsey...
Click to read more »Sphere theorem (3-manifolds)
Minggu, 2025-11-23 19:30:28Christos Papakyriakopoulos (1957) gives conditions for elements of the second homotopy group of a 3-manifold to be represented by embedded spheres. One example...
Click to read more »Charles Rezk
Rabu, 2026-04-01 03:40:231999.0043. S2CID 168002. Rezk, Charles (2001). "A model for the homotopy theory of homotopy theory". Transactions of the American Mathematical Society. 353...
Click to read more »Dubins path
Kamis, 2026-04-16 10:44:58Kirszenblat and J. Hyam Rubinstein. A proof characterizing Dubins paths in homotopy classes has been given by J. Ayala. The Dubins path is commonly used in...
Click to read more »Weakly contractible space
Kamis, 2026-02-19 16:38:37contractible if all of its homotopy groups are trivial. Equivalently, a space is weakly contractible if it is weakly homotopy equivalent to a point. Every...
Click to read more »Dynamical systems theory
Jumat, 2026-01-16 11:54:21Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
Click to read more »Kenneth Brown (mathematician)
Rabu, 2026-04-01 03:24:53Technology, under the supervision of Daniel Quillen, with thesis Abstract Homotopy Theory and Generalized Sheaf Cohomology. Hired by Cornell University in...
Click to read more »Topological quantum number
Rabu, 2026-01-14 00:20:44due to the appearance of the fundamental group or a higher-dimensional homotopy group in the description of the problem, quite often because the boundary...
Click to read more »Quotient category
Sabtu, 2026-03-14 00:17:07coincides with the notion of a quotient monoid or a quotient group. The homotopy category of topological spaces hTop is a quotient category of Top, the...
Click to read more »Localization of a topological space
Senin, 2024-03-18 10:01:38from X to Y is universal for (homotopy classes of) maps from X to A-local CW complexes. This space Y is unique up to homotopy equivalence, and is called...
Click to read more »Graeme Segal
Rabu, 2026-03-04 12:51:57conjecture, which he formulated. He has made many other contributions to homotopy theory in the past four decades, including an approach to infinite loop...
Click to read more »Additive category
Selasa, 2026-04-07 06:49:35concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Product (category theory)
Rabu, 2026-03-04 03:41:54concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Tangloids
Jumat, 2026-04-24 23:44:01case of fiber bundles. The classification of covering maps is done via homotopy theory; in this case, the formal expression of double-covering is to say...
Click to read more »Theory of computation
Jumat, 2026-05-08 11:05:36Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
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Sabtu, 2026-04-25 01:01:10implications: for example the existence of this bundle shows that the higher homotopy groups of spheres are not trivial in general. It also provides a basic...
Click to read more »Simplicial complex
Jumat, 2026-05-29 13:02:21more abstract notion of a simplicial set appearing in modern simplicial homotopy theory. The purely combinatorial counterpart to a simplicial complex is...
Click to read more »Bass–Quillen conjecture
Rabu, 2026-04-22 08:24:46{\displaystyle H_{Nis}^{1}(Spec(A),GL_{r}).} Positive results about the homotopy invariance of H N i s 1 ( U , G ) {\displaystyle H_{Nis}^{1}(U,G)} of isotropic...
Click to read more »Kervaire invariant
Selasa, 2026-05-12 00:15:24tangent bundle) which was used by Lev Pontryagin in 1950 to compute the homotopy group π n + 2 ( S n ) = Z / 2 Z {\displaystyle \pi _{n+2}(S^{n})=\mathbb...
Click to read more »Edgar H. Brown
Rabu, 2026-04-01 03:24:51Whitehead, and his doctoral dissertation was on Finite Computability of the Homotopy Groups of Finite Groups. In 1962–63, he visited the Institute for Advanced...
Click to read more »John Morgan (mathematician)
Kamis, 2026-03-05 11:32:01both from Rice University. His Ph.D. thesis, entitled Stable tangential homotopy equivalences, was written under the supervision of Morton L. Curtis. He...
Click to read more »Cauchy's integral theorem
Sabtu, 2026-04-04 13:01:44that a curve is homotopic to a constant curve if there exists a smooth homotopy (within U {\displaystyle U} ) from the curve to the constant curve. Intuitively...
Click to read more »Glossary of areas of mathematics
Kamis, 2026-05-21 12:53:54Fourier transforms that can be defined on locally compact groups. Abstract homotopy theory A part of topology that deals with homotopic functions, i.e. functions...
Click to read more »Special unitary group
Selasa, 2026-05-12 14:12:07by means of a standard topological result (the long exact sequence of homotopy groups for fiber bundles). The SU(2)-bundles over S5 are classified by...
Click to read more »Categorification
Senin, 2026-04-13 02:08:25concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
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Senin, 2026-05-18 13:45:47nontrivial homotopy group, preserved by the differential equations. Thus, the differential equation solutions can be classified into homotopy classes. No...
Click to read more »Frederick R. Cohen
Kamis, 2026-03-26 02:36:11the rest of his career. Cohen did influential work in several areas of homotopy theory. His thesis concerned the topology of configuration spaces, a topic...
Click to read more »Lagrangian Grassmannian
Minggu, 2026-04-26 10:41:57\Lambda (n)} the fundamental group may be inferred from the long exact homotopy sequence: π 1 ( Λ ( n ) ) = Z . {\displaystyle \pi _{1}(\Lambda (n))=\mathbb...
Click to read more »Smash product
Minggu, 2025-11-30 13:07:56Y)/(X\vee Y).} The smash product shows up in homotopy theory, a branch of algebraic topology. In homotopy theory, one often works with a different category...
Click to read more »Lubin–Tate formal group law
Senin, 2025-06-09 16:03:57groups. A later application of the theory has been in the field of stable homotopy theory, with the construction of a particular extraordinary cohomology...
Click to read more »Link group
Selasa, 2023-12-19 02:46:59link, up to link homotopy. In other words, each component of the extended link is allowed to move through regular homotopy (homotopy through immersions)...
Click to read more »Derived functor
Selasa, 2026-05-19 04:21:00cofibrations and weak equivalences. Typically one is interested in the underlying homotopy category obtained by localizing against the weak equivalences. A Quillen...
Click to read more »Jeffrey H. Smith
Kamis, 2026-03-05 11:01:45"nilpotence and stable homotopy". Devinatz, Ethan S.; Hopkins, Michael J.; Smith, Jeffrey H. (1988). "Nilpotence and stable homotopy theory. I". Annals of...
Click to read more »Kleisli category
Rabu, 2026-03-04 00:06:03concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Alexander duality
Selasa, 2026-06-02 20:40:36showing that the geometric realization | X ∗ | {\displaystyle |X^{*}|} is homotopy equivalent to | Y | ∖ | X | {\displaystyle |Y|\setminus |X|} . Björner...
Click to read more »Siegel modular variety
Selasa, 2026-04-14 05:00:48Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
Click to read more »2-category
Selasa, 2026-04-07 06:53:46complex (i.e., an ∞-category). The Duskin nerve is an instance of the homotopy coherent nerve. By definition, a functor is simply a structure-preserving...
Click to read more »K-homology
Rabu, 2025-10-22 02:49:07-algebras, it classifies the Fredholm modules over an algebra. An operator homotopy between two Fredholm modules ( H , F 0 , Γ ) {\displaystyle ({\mathcal...
Click to read more »N-monoid
Rabu, 2017-11-15 06:35:28concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Injective object
Senin, 2025-07-28 22:41:38concept of injective module. This concept is important in cohomology, in homotopy theory and in the theory of model categories. The dual notion is that of...
Click to read more »Ioan James
Minggu, 2026-04-19 04:18:20British mathematician working in the field of topology, particularly in homotopy theory. James was born in Croydon, Surrey, England, and was educated at...
Click to read more »Mona Merling
Minggu, 2025-12-28 22:10:53algebraic topology, including algebraic K-theory and equivariant stable homotopy theory. She is an associate professor of mathematics at the University...
Click to read more »Jordan curve theorem
Selasa, 2026-05-26 23:20:18unit ball. Let K 0 {\displaystyle K_{0}} and K 1 {\displaystyle K_{1}} be homotopy-equivalent compacts in R n {\displaystyle \mathbb {R} ^{n}} . Then if R...
Click to read more »Ring of modular forms
Rabu, 2024-10-30 14:16:36Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
Click to read more »Brouwer fixed-point theorem
Senin, 2026-05-25 21:33:02Brouwer's approach was his systematic use of recently developed tools such as homotopy, the underlying concept of the Poincaré group. In the following year, Hadamard...
Click to read more »Complex projective plane
Minggu, 2024-11-10 09:57:40projective line, or Riemann sphere, lying in the plane. The nontrivial homotopy groups of the complex projective plane are π 2 = π 5 = Z {\displaystyle...
Click to read more »Aspherical space
Kamis, 2026-03-12 01:57:42mathematics, an aspherical space is a path connected topological space with all homotopy groups π n ( X ) {\displaystyle \pi _{n}(X)} equal to 0 when n ≠ 1 {\displaystyle...
Click to read more »Higher-dimensional algebra
Minggu, 2025-05-04 23:12:172009-06-04 at the Wayback Machine Nonabelian Algebraic Topology: Higher homotopy groupoids of filtered spaces Brown, Ronald; Higgins, Philip; Sivera, Rafael...
Click to read more »Co- and contravariant model structure
Selasa, 2025-04-29 02:15:31is left proper and combinatorical. For any model category, there is a homotopy category associated to it by formally inverting all weak equivalences....
Click to read more »Rig category
Rabu, 2025-11-26 02:26:07concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Zeeman conjecture
Rabu, 2025-10-01 11:41:47restated as the claim that for any 2-complex G {\displaystyle G} which is homotopy equivalent to a point, some barycentric subdivision of G × [ 0 , 1 ] {\displaystyle...
Click to read more »Cartan formula
Jumat, 2025-10-17 09:59:41respectively, acting on differential forms. It is also called the Cartan homotopy formula or Cartan magic formula. This formula is named after Élie Cartan...
Click to read more »Accessible category
Jumat, 2025-06-06 11:22:06categories also have applications in homotopy theory. Grothendieck continued the development of the theory for homotopy-theoretic purposes in his (still partly...
Click to read more »Cartesian fibration
Minggu, 2026-05-10 08:19:32In mathematics, especially homotopy theory, a cartesian fibration is, roughly, a map so that every lift exists that is a final object among all lifts....
Click to read more »Exact functor
Jumat, 2025-09-19 23:39:56concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Lie theory
Senin, 2026-04-06 19:25:19Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
Click to read more »André Joyal
Minggu, 2026-01-04 20:48:02pp. ISBN 0-521-55830-1 André Joyal, Myles Tierney, Notes on simplicial homotopy theory, CRM Barcelona, Jan 2008 pdf André Joyal, Disks, duality and theta-categories...
Click to read more »Simplicially enriched category
Kamis, 2026-03-19 02:54:48different from the limits in the sense of enriched category theory. The homotopy coherent nerve of a simplicially enriched category is a simplicial set...
Click to read more »Differential graded algebra
Selasa, 2026-04-28 05:45:40American mathematician Dennis Sullivan developed a DGA to encode the rational homotopy type of topological spaces. Let A ∙ = ⨁ i ∈ Z A i {\displaystyle A_{\bullet...
Click to read more »Triangulation (topology)
Selasa, 2026-04-28 18:22:46shown that they were invariant regarding homeomorphism and even regarding homotopy equivalence. Furthermore it was shown that singular and simplicial homology...
Click to read more »Fibrant object
Kamis, 2025-03-06 03:17:47In mathematics, specifically in homotopy theory in the context of a model category M, a fibrant object A of M is an object that has a fibration to the...
Click to read more »Thom space
Minggu, 2025-09-07 21:27:02differential topology and stable homotopy theory, and is in particular integral to our knowledge of the stable homotopy groups of spheres. If the Steenrod...
Click to read more »Semi-locally simply connected
Rabu, 2026-04-22 21:35:37starting and ending at x is nullhomotopic in X via a basepoint-preserving homotopy). Note that if U satisfies this condition, so does any smaller neighborhood...
Click to read more »Dagger symmetric monoidal category
Rabu, 2024-04-17 20:24:58concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Modelica
Selasa, 2026-05-12 13:35:20use in embedded systems) 3.2 2010, March Improved initialization with homotopy method, functions as formal inputs to functions, Unicode support, access...
Click to read more »Pure mathematics
Sabtu, 2026-06-06 20:11:05Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
Click to read more »Nonlinear algebra
Minggu, 2026-04-26 00:36:21the other hand, numerical methods typically use algebraically founded homotopy continuation, with a base field of the complex numbers. Algebraic equation...
Click to read more »Carlos Benjamin de Lyra
Senin, 2026-06-01 18:45:27Cartan and participated in seminars and watched Hurewicz's lectures on homotopy in the Collège de France in Paris. During his time in France, Lyra met...
Click to read more »John Milnor
Selasa, 2026-05-05 05:24:23their associated link structure, classifying Brunnian links up to link-homotopy and introduced new invariants of it, called Milnor invariants. Upon completing...
Click to read more »Dan Burghelea
Selasa, 2026-03-10 08:00:00significant contributions are on Topology of infinite dimensional manifolds; Homotopy type of the space of homeomorphisms and diffeomorphisms of compact smooth...
Click to read more »Q-construction
Senin, 2025-11-10 13:29:51the i-th K-group of C with coefficients in a group G is defined as the homotopy group with coefficients: K i ( C ; G ) = π i ( B + C ; G ) {\displaystyle...
Click to read more »Nurse with Wound
Kamis, 2026-03-12 12:54:17only Stapleton was left from the original trio and he now regards 1982's Homotopy to Marie as being the first proper Nurse with Wound release. There are...
Click to read more »Arithmetic
Sabtu, 2026-05-23 05:53:57Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
Click to read more »Lifting property
Sabtu, 2026-03-21 22:55:20property is a property of a pair of morphisms in a category. It is used in homotopy theory within algebraic topology to define properties of morphisms starting...
Click to read more »Differential equation
Kamis, 2026-03-19 04:49:23Diophantine geometry Topology General Algebraic Differential Geometric Homotopy theory Knot theory Applied Engineering mathematics Mathematical biology...
Click to read more »Closure (topology)
Selasa, 2026-04-07 19:53:31Space compact connected Hausdorff metric uniform second-countable Homotopy homotopy group fundamental group Simplicial complex CW complex Polyhedral complex...
Click to read more »Camille Jordan
Senin, 2026-06-01 18:34:50numbers Jordan–Schur theorem Jordan–Schönflies theorem Bounded variation Homotopy group k-edge-connected graph Total variation Scientific career Fields Mathematics...
Click to read more »Induced homomorphism
Rabu, 2026-04-22 20:56:38morphism in the source category. For example, fundamental groups, higher homotopy groups, singular homology, and De Rham cohomology are algebraic structures...
Click to read more »Extension
Selasa, 2026-05-19 03:22:49Galois theory Group extension, in abstract algebra and homological algebra Homotopy extension property, in topology Kolmogorov extension theorem, in probability...
Click to read more »Cobordism
Kamis, 2026-03-26 06:54:18when René Thom showed that cobordism groups could be computed by means of homotopy theory, via the Thom complex construction. Cobordism theory became part...
Click to read more »Chenchang Zhu
Senin, 2026-03-23 13:38:08higher Lie algebroids, and higher Lie groupoids and their connections to homotopy theory. She is noted for introducing Kan simplicial manifolds in 2006,...
Click to read more »Victor Buchstaber
Senin, 2025-12-15 16:46:43Soviet and Russian mathematician known for his work on algebraic topology, homotopy theory, and mathematical physics. Buchstaber's first research work was...
Click to read more »Noetherian ring
Jumat, 2026-05-01 03:46:48etc., is an ascending chain that does not terminate. The ring of stable homotopy groups of spheres is not Noetherian. However, a non-Noetherian ring can...
Click to read more »Conglomerate (mathematics)
Kamis, 2026-01-15 05:04:36concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Loop (topology)
Rabu, 2026-04-22 20:58:35begins and ends at the same point x 0 {\displaystyle x_{0}} . The set of homotopy classes of loops based at x 0 {\displaystyle x_{0}} together with the operation...
Click to read more »Presheaf with transfers
Sabtu, 2026-05-09 06:33:24presheaf F with transfers is said to be A 1 {\displaystyle \mathbb {A} ^{1}} -homotopy invariant if F ( X ) ≃ F ( X × A 1 ) {\displaystyle F(X)\simeq F(X\times...
Click to read more »Category of topological spaces
Sabtu, 2026-05-30 10:17:50\mathbf {Top} } . The homotopy category h T o p {\displaystyle \mathbf {hTop} } has topological spaces for objects and homotopy equivalence classes of...
Click to read more »Outline of category theory
Kamis, 2026-01-15 18:06:24concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categories...
Click to read more »Pointed space
Minggu, 2026-05-17 10:42:29} Pointed spaces are important in algebraic topology, particularly in homotopy theory, where many constructions, such as the fundamental group, depend...
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