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sequencesandseries× 320  harmonicanalysis× 319 
abelianvarieties× 318
projective algebraic varieties endowed with an Abelian group structure. Over the complex numbers, they can be described as quotients of a vector space by a lattice of full rank. …

sheaftheory× 317 
computerscience× 311
For question borderline with, or having application to, computer science. Consider also posting http://cs.stackexchange.com/ or http://cstheory.stackexchange.com/ instead of here, if appropriate.

discretegeometry× 309
Finite or discrete collections of geometric objects. Packings, tilings, polyhedra, polytopes, intersection, arrangements, rigidity.

vectorbundles× 305 
openproblem× 304
equivalent to a known open problem, then the openproblem tag is added. After that, the question essentially becomes, "What is known about this problem? What are some…

examples× 301 
forcing× 298
a method first used to prove the continuum hypothesis is independent of the classical axioms of set theory

convexpolytopes× 294
the convex hulls of a finite set of points in Euclidean spaces. They have rich combinatorial, arithmetic, and metrical theory, and are related to toric varieties and to linear pr…

inequalities× 291 
simplicialstuff× 288 
ergodictheory× 287
Dynamical systems on measure spaces, invariant measures, ergodic averages, mixing properties.

hyperbolicgeometry× 286  lattices× 282 
galoistheory× 276 
sp.spectraltheory× 275
Schrodinger operators, operators on manifolds, general differential operators, numerical studies, integral operators, discrete models, resonances, nonselfadjoint operators, random operators/matrices…

groupcohomology× 259  integration× 251 
terminology× 251  riemannsurfaces× 250  convexity× 250 
specialfunctions× 249
Many special functions appear as solutions of differential equations or integrals of elementary functions. Most special functions have relationships with representation theory of Lie groups.

deformationtheory× 239  convexgeometry× 235 
it.informationtheory× 234
Covers theoretical and experimental aspects of information theory and coding.

diophantineequations× 230 
etalecohomology× 227  modelcategories× 225  galoisrepresentations× 221  automorphicforms× 221 
bigpicture× 220
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 subfields of mat…

stacks× 216  axiomofchoice× 215  stochasticcalculus× 215 