47A05  General (adjoints, conjugates, products, inverses, domains, ranges, etc.)


47A06  Linear relations (multivalued linear operators)


47A07  Forms (bilinear, sesquilinear, multilinear)


47A10  Spectrum, resolvent


47A11  Local spectral properties


47A12  Numerical range, numerical radius


47A13  Severalvariable operator theory (spectral, Fredholm, etc.)


47A15  Invariant subspaces


47A16  Cyclic and hypercyclic vectors


47A20  Dilations, extensions, compressions


47A25  Spectral sets


47A30  Norms (inequalities, more than one norm, etc.)


47A35  Ergodic theory [See also 28Dxx, 37Axx]


47A40  Scattering theory [See also 34L25, 35P25, 81Uxx]


47A45  Canonical models for contractions and nonselfadjoint operators


47A46  Chains (nests) of projections or of invariant subspaces, integrals along chains, etc.


47A48  Operator colligations (= nodes), vessels, linear systems, characteristic functions, realizations, etc.


47A50  Equations and inequalities involving linear operators, with vector unknowns


47A52  Illposed problems, regularization


47A53  (Semi) Fredholm operators; index theories [See also 58B15, 58J20]


47A55  Perturbation theory


47A56  Functions whose values are linear operators (operator and matrix valued functions, etc., including analytic and meromorphic ones)


47A57  Operator methods in interpolation, moment and extension problems [See also 30E05, 42A70, 42A82, 44A60]


47A58  Operator approximation theory


47A60  Functional calculus


47A62  Equations involving linear operators, with operator unknowns


47A63  Operator inequalities


47A64  Operator means, shorted operators, etc.


47A65  Structure theory


47A66  Quasitriangular and nonquasitriangular, quasidiagonal and nonquasidiagonal operators


47A67  Representation theory


47A68  Factorization theory (including WienerHopf and spectral factorizations)


47A70  (Generalized) eigenfunction expansions; rigged Hilbert spaces


47A75  Eigenvalue problems [See also 49R50]


47A80  Tensor products of operators [See also 46M05]


47A99  None of the above, but in this section

