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: 
characteristicp× 181 
teaching× 180
For questions related to teaching mathematics. For questions in Mathematics Education as a scientific discipline there is also the tag mathematicseducation.

hodgetheory× 179  approximationtheory× 177 
birationalgeometry× 175  stablehomotopy× 173  algebraicsurfaces× 170  manifolds× 170 
computationalgeometry× 169
Using computers to solve geometric problems. Questions with this tag should typically have at least one other tag indicating what sort of geometry is involved, such as ag.algebraicgeometry or mg.metr…

mathphilosophy× 165 
riemannzetafunction× 161
the function of one complex variable $s$ defined by the series $\zeta(s) = \sum_{n \geq 1} \frac{1}{n^s}$ when $\operatorname{Re}(s)>1$. It admits a meromorphic continuati…

hilbertspaces× 160
a real or complex vector space endowed with an inner product such that $H$ is a complete metric space when endowed with the norm induced by this inner product.

euclideangeometry× 157  randomwalk× 157  monoidalcategories× 156 
textbookrecommendation× 154
Questions asking for recommendations of textbooks on some subject. It can be helpful to indicate whether the request is for selfstudy, for use in a course one teaches, for use accompanying a course o…

semigroups× 149 
computeralgebra× 149
Using computers to solve algebraic problems. Questions with this tag should typically include at least one other tag indicating what sort of algebraic problem is involved, such as ac.commutativealgeb…

convexoptimization× 149
Optimization with convex constraints and convex objectives; notions related to convex optimization such as subgradients, normal cones, separating hyperplanes

calculusofvariations× 148 
prooftheory× 147
For question in Proof Theory, where "proofs" themselves are the object of mathematical investigation. It is not to be used to request a proof of some result.

groupactions× 145  zetafunctions× 144 
differentialoperators× 143
Elliptic, parabolic and hyperbolic operators. Laplace, LaplaceBeltrami, Schrödinger, Dirac. Exterior derivative and Lie derivative operators.

lfunctions× 143
Questions about generalizations of the Riemann Zeta function of arithmetic interest whose definition relies on meromorphic continuation of special kinds of Dirichlet series, such as Dirichlet Lfuncti…

langlandsconjectures× 142
Higher reciprocity laws

universalalgebra× 141
The study of algebraic structures and properties applying to large classes of such structures. For example, ideas from group theory and ring theory are extended and considered for structures with oth…

homology× 140 
gm.generalmathematics× 137 
books× 135
Questions in which books play a keyrole, such as questions on antique books, ebooks, difference between various editions of a book, etc. For questions asking for recommendations of books on some sub…

spectralgraphtheory× 135
Questions related to the spectrum of graphs, defined using one of the possible variants of the discrete Laplace operator or Laplacian matrix.
See https://en.wikipedia.org/wiki/Discrete_Laplace_oper…

graphcolorings× 134 
intersectiontheory× 134  geometricmeasuretheory× 132  eigenvalues× 132  classfieldtheory× 131 