## Mathematics Subject Classification – MSC2020

Topological and differentiable algebraic systems {For topological rings and fields, see 12Jxx, 13Jxx, 16W80} 6272

Representations of Lie and linear algebraic groups over real fields: analytic methods {For the purely algebraic theory, see 20G05} 2313

General theory of group and pseudogroup actions {For topological properties of spaces with an action, see 57S20} 235

Homogeneous spaces {For general actions on manifolds or preserving geometrical structures, see 57M60, 57Sxx; for discrete subgroups of Lie groups, see especially 22E40} 366