Sum rule

Sum rule may refer to:


 * Sum rule in differentiation, Differentiation rules
 * Sum rule in integration, see Integral
 * Addition principle, a counting principle in combinatorics
 * In probability theory, an implication of the additivity axiom, see Probability axioms
 * Sum rule in quantum mechanics
 * QCD sum rules, non-perturbative techniques in quantum chromodynamics
 * Sum rules (quantum field theory), relations between static and dynamic quantities in quantum field theory