# 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:
 sage× 83 For questions concerning Sage. Consider whether your question would be a better fit at [ask Sage](http://ask.sagemath.org/). publishing× 83 for questions about publishing mathematical content levy-processes× 82 Question related to Lévy processes, i.e. stochastically continuous processes with independent, stationary increments. group-homomorphism× 82 idempotents× 81 For questions about elements which satisfy $x\cdot x=x$ where $\cdot$ is a composition law. grassmannian× 81 In mathematics, the Grassmannian $\mathbf{Gr}(r, V)$ is a space which parameterizes all linear subspaces of a vector space $V$ of given dimension $r$. poissons-equation× 81 a partial differential equation of elliptic type with broad utility in electrostatics, mechanical engineering and theoretical physics. (Def: http://en.m.wikiped… spherical-harmonics× 80 Questions on spherical harmonics, a set of basis functions that satisfy an orthogonality relation over the sphere. universal-property× 80 topological-k-theory× 78 a generalized cohomology theory, for which $K_0(X)$ is the Grothendieck group of isomorphism classes of vector bundles over topological space $X$. See also (algebraic-k-theory)… big-numbers× 77 For questions relating to the computation, estimation and properties of extremely large quantities that are not usually used in mainstream mathematics. greatest-common-divisor× 76 The greatest common divisor of two or more integers is the largest integer that divides all of them (if it exists). geometric-algebras× 76 Clifford algebras over the real numbers. They are applied in geometry and theoretical physics. combinatorial-designs× 75 For questions about Combinatorial design theory, a part of combinatorial mathematics that deals with the existence, construction and properties of systems of finite sets whose arrangements satisfy gen… research× 75 maximal-ideals× 75 ideals which are contained in only one other ideal which is the ring itself. meta-math× 75 the term for the theory in which mathematics is formalized (often PA, ZFC or similar theories). Meta-mathematical statements are statements which are evaluated at the level of the meta-… z-transform× 75 a discrete analogue to the Laplace transform, in that it maps a time domain signal into a representation in complex frequency plane. noncommutative-geometry× 74 a study of noncomutative algebras from geometrical point of view. The motivation of this approach is Gelfand representation theorem, which shows that every commutative C*-al… semidefinite-programming× 74 euler-lagrange-equation× 74 In calculus of variations, the Euler–Lagrange equation, Euler's equation, or Lagrange's equation, is a second-order partial differential equation whose solutions are the functions for which a given fu… division-algebras× 74 a vector spaces over a field $F$ equipped with a bilinear product and a multiplicative neutral element $1$. All the non-zero elements of $D$ have a multiplicative inverse. As… formal-grammar× 73 In formal language theory, a grammar (when the context is not given, often called a formal grammar for clarity) is a set of production rules for strings in a formal language. A formal grammar is a set… hodge-theory× 73 The study of relations between, one the one hand, the topology of a smooth manifold as encoded in the cohomology groups, and on the other, the set of solutions to the Laplace operator on differential … complex-dynamics× 73 the study of dynamical systems of functions over complex numbers. computational-algebra× 73 an area of algebra that seeks efficient algorithms to answer fundamental problems concerning basic algebraic objects (groups, rings, fields, etc.). For questions about generic… bifurcation× 73 the mathematical study of changes in the qualitative or topological structure of a given family, such as the integral curves of a family of vector fields, and the solutions of a … stationary-processes× 73 For questions about strictly stationary or stationary in the wide sense sequences or processes. Questions about deterministic stationary processes (in the case of discrete dynamical systems) are welco… quadrilateral× 72 For questions about general quadrilaterals (including parallelograms, trapezoids, rhombi) and their properties. multiplicative-function× 72 In number theory, a multiplicative function is a function defined on positive integers such that f(ab)=f(a)f(b) for a,b coprime. E.g. Euler's totient function, sum of divisors and number of divisor… nilpotence× 72 A nilpotent matrix has $A^n=0$ for some integer $n$. ceiling-function× 71 The function that maps a real number $x$ to the smallest integer greater than or equal to $x$ (which is often denoted $\lceil x\rceil$. See also (floor-function). affine-schemes× 71 The spectrum of a commutative ring with unit is the set of prime ideals endowed with the Zariski topology. One can define a sheaf of rings on this space : to each Zariski-open set is assigned a commut… coherent-sheaves× 71 In mathematics, especially in algebraic geometry and the theory of complex manifolds, coherent sheaves are a specific class of sheaves having particularly manageable properties closely linked to the g… fibration× 71 A branch of topology that deals with the notion of a fiber bundle. nets× 70 a generalization of a sequence where a directed set is used as the index set instead of positive integers. Convergence of nets can be defined in a similar way as convergence of sequences. …