Tags

A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.

 Type to find tags:
 order-theory× 270 etale-cohomology× 264 galois-representations× 264 abstract-algebra× 263 schemes× 262 the geometrical study of solutions of algebraic systems of equations, not only over the real/complex numbers, but also over integer numbers (and more generally o… finite-fields× 261 stacks× 261 elliptic-pde× 260 Questions about partial differential equations of elliptic type. Often used in combination with the top-level tag ap.analysis-of-pdes. topological-groups× 258 random-matrices× 253 Statistics of spectral properties of matrix-valued random variables. axiom-of-choice× 251 additive-combinatorics× 245 Questions on the subject additive combinatorics, also known as arithmetic combinatorics, such as questions on: additive bases, sum sets, inverse sum set theorems, sets with small doubling, Sidon sets,… 3-manifolds× 244 big-picture× 242 Questions designed to get an overview of a specific subject or body of results or to understand the relations among similar definitions, techniques or concepts appearing in different sub-fields of mat… derived-category× 241 For questions about the derived categories of various abelian categories and questions regarding the derived category construction itself. fields× 241 Fields as algebraic objects. For vector and tensor fields, use eg. [dg.differential-geometry]. For physical fields, use eg. [mp.mathematical-physics] or [quantum-field-theory]. singularity-theory× 240 modules× 239 quadratic-forms× 237 descriptive-set-theory× 236 the study of definable subsets of Polish spaces, where definable is taken to mean from the Borel or projective hierarchies. Other topics include infinite games and determinac… quantum-groups× 231 Questions about algebraic structures known as quantum groups, and their categories of representations. Quasitriangular Hopf algebras and their Drinfel'd twists, triangular Hopf algebras, $C^\star$ qua… intuition× 230 Questions asking for the intuition behind some definition, conjecture, proof etc. In other words, questions designed to improve or to acquire understanding on a conceptual or intuitive level, as oppos… projective-geometry× 229 commutative-rings× 229 noncommutative-algebra× 228 topos-theory× 228 matrix-analysis× 226 The study of the properties of real and complex matrices that are more close to analysis and operator theory. For instance: the properties of positive definite matrices, matrix inequalities, perturbat… linear-programming× 225 noncommutative-geometry× 224 Noncommutative geometry in the sense of Connes and beyond: noncommutative algebras viewed as functions on a noncommutative space. von-neumann-algebras× 224 Subtag of [tag:oa.operator-algebras] for questions about von Neumann algebras, that is, weak operator topology closed, unital, *-subalgebras of bounded operators on a Hilbert space. hopf-algebras× 218 a vector space $H$ over a field $k$ endowed with an associative product $\times:H\otimes_k H\to H$ and a coassociative coproduct $\Delta:H\to H\otimes_k H$ which is a morphism of alg… algebraic-k-theory× 217 mathematics-education× 213 For questions in Mathematics Education as a scientific discipline. For more hands-on questions on teaching Mathematics, please use the tag teaching. There is also a Stack Exchange community http://mat… approximation-theory× 209 convex-optimization× 203 Optimization with convex constraints and convex objectives; notions related to convex optimization such as sub-gradients, normal cones, separating hyperplanes markov-chains× 203