47B50 Operators on spaces with an indefinite metric [See also <a href="#code:46C50">46C50</a>]

47B65 Positive operators and order-bounded operators

47B80 Random operators [See also <a href="#code:47H40">47H40</a>, <a href="#code:60H25">60H25</a>]

47B99 None of the above, but in this section

47Cxx Individual linear operators as elements of algebraic systems

47C15 Operators in $C^*$- or von Neumann algebras

47C99 None of the above, but in this section

47Dxx Groups and semigroups of linear operators, their generalizations and applications

47D03 Groups and semigroups of linear operators {For nonlinear operators, see <a href="#code:47H20">47H20</a>; see also <a href="#code:20M20">20M20</a>}

47D06 One-parameter semigroups and linear evolution equations [See also <a href="#code:34G10">34G10</a>, <a href="#code:34K30">34K30</a>]

47D07 Markov semigroups and applications to diffusion processes {For Markov processes, see <a href="#code:60Jxx">60Jxx</a>}

47D08 Schrödinger and Feynman-Kac semigroups

47D09 Operator sine and cosine functions and higher-order Cauchy problems [See also <a href="#code:34G10">34G10</a>]

47D99 None of the above, but in this section

47Exx Ordinary differential operators [See also <a href="#code:34Bxx">34Bxx</a>, <a href="#code:34Lxx">34Lxx</a>]

47E05 Ordinary differential operators [See also <a href="#code:34Bxx">34Bxx</a>, <a href="#code:34Lxx">34Lxx</a>] (should also be assigned at least one other classification number in section 47)

47E99 None of the above, but in this section

47Fxx Partial differential operators [See also <a href="#code:35Pxx">35Pxx</a>, <a href="#code:58Jxx">58Jxx</a>]

47F05 Partial differential operators [See also <a href="#code:35Pxx">35Pxx</a>, <a href="#code:58Jxx">58Jxx</a>] (should also be assigned at least one other classification number in section 47)

47F99 None of the above, but in this section

47Gxx Integral, integro-differential, and pseudodifferential operators [See also <a href="#code:58Jxx">58Jxx</a>]

47G10 Integral operators [See also <a href="#code:45P05">45P05</a>]