00.00.00 GENERAL
- 01.00.00 Communication, education, history, and philosophy
- 02.00.00 Mathematical methods in physics
- 03.00.00 Quantum mechanics, field theories, and special relativity (see also section 11 General theory of fields and particles) (3)
- 04.00.00 General relativity and gravitation (for astrophysical aspects, see 95.30.Sf Relativity and gravitation; for relativistic aspects of cosmology, see 98.80.Jk); Special relativity, see 03.30.+p
- 05.00.00 Statistical physics, thermodynamics, and nonlinear dynamical systems (see also 02.50.-r Probability theory, stochastic processes, and statistics) (4)
- 06.00.00 Metrology, measurements, and laboratory procedures (for laser applications in metrology, see 42.62.Eh) (1)
- 07.00.00 Instruments, apparatus, and components common to several branches of physics and astronomy (see also each subdiscipline for specialized instrumentation and techniques) (2)