Quantum field theory 94 Field theory 53 Physics 14 Quantum theory 13 Field theory (Physics) 12 Unified field theories 11 Class field theory 9 Mathematical physics 7 Particles (Nuclear physics) 6 Quantum electrodynamics 6 Condensed matter 5 Cosmology 5 Relativity (Physics) 5 Algebra 4 Electromagnetism,Field theory (Physics) 4 Mathematics 4 Nuclear physics 4 Quantum chromodynamics 4 Quantum gravity 4 Gauge fields (Physics) 3 General relativity (Physics) 3 LIGAND FIELD THEORY AND ITS APPLICATION 3 Ligand field theory 3 Physicists 3 Quantum physics (quantum mechanics & quantum field theory) 3 String models 3 Superstring theories 3 Algebraic fields 2 Algebraic number theory 2 Conformal invariants 2