Algebra, Homological Algèbre homologique MATHEMATICS Algebra Algebraic Algebraic geometry -- (Co)homology theory -- Sheaves, derived categories of sheaves and related constructions Algebraic geometry -- Foundations -- Noncommutative algebraic geometry [See also 16S38] Algèbres non commutatives Category theory; homological algebra Geometría algebraica Geometry Geometry, Algebraic Géométrie algébrique Homologie Homologische algebra Homologisk algebra Homology theory K-theory K-theory -- $K$-theory and operator algebras -- Index theory K-theory -- $K$-theory and operator algebras -- Kasparov theory ($KK$-theory) K-theory -- $K$-theory of forms [See also 11Exx] -- Witt groups of rings [See also 11E81] K-theory -- Grothendieck groups and $K_0$ -- $K_0$ of group rings and orders K-theory -- Higher algebraic $K$-theory K-théorie Linear Noncommutative algebras Operator theory -- Linear spaces and algebras of operators -- Crossed product algebras (analytic crossed products) Topology