Reciprocity theorem may refer to: *

Quadratic reciprocity In number theory, the law of quadratic reciprocity is a theorem about modular arithmetic that gives conditions for the solvability of quadratic equations modulo prime numbers. Due to its subtlety, it has many formulations, but the most standard st ...

, a theorem about modular arithmetic **

Cubic reciprocity Cubic reciprocity is a collection of theorems in elementary and algebraic number theory that state conditions under which the congruence ''x''3 ≡ ''p'' (mod ''q'') is solvable; the word "reciprocity" comes from the form of ...

Quartic reciprocity Quartic or biquadratic reciprocity is a collection of theorems in elementary and algebraic number theory that state conditions under which the congruence ''x''4 ≡ ''p'' (mod ''q'') is solvable; the word "reciprocity" comes from the form ...

Artin reciprocity The Artin reciprocity law, which was established by Emil Artin in a series of papers (1924; 1927; 1930), is a general theorem in number theory that forms a central part of global class field theory. The term " reciprocity law" refers to a long li ...

** Weil reciprocity for algebraic curves * Frobenius reciprocity theorem for group representations *

Stanley's reciprocity theorem In combinatorial mathematics, Stanley's reciprocity theorem, named after MIT mathematician Richard P. Stanley, states that a certain functional equation is satisfied by the generating function of any rational cone (defined below) and the generatin ...

for generating functions * Reciprocity (engineering), theorems relating signals and the resulting responses ** including

Reciprocity (electrical networks) Reciprocity in electrical networks is a property of a circuit that relates voltages and currents at two points. The reciprocity theorem states that the current at one point in a circuit due to a voltage at a second point is the same as the current ...

, a theorem relating voltages and currents in a network *

Reciprocity (electromagnetism) In classical electromagnetism, reciprocity refers to a variety of related theorems involving the interchange of time-harmonic electric current densities (sources) and the resulting electromagnetic fields in Maxwell's equations for time-invarian ...

, theorems relating sources and the resulting fields in classical electromagnetism * Tellegen's theorem, a theorem about the transfer function of passive networks *Reciprocity law for Dedekind sums *

Betti's theorem Betti's theorem, also known as Maxwell–Betti reciprocal work theorem, discovered by Enrico Betti in 1872, states that for a linear elastic structure subject to two sets of forces i=1,...,n and , j=1,2,...,n, the work done by the set P through th ...

in linear elasticity *The Triple Product rule, a formula relating the partial derivatives of three independent variables, often used in thermodynamics

See also