Reciprocity may refer to:
Law and trade Reciprocity (Canadian politics), free trade with the United States of America Reciprocal trade agreement, entered into in order to reduce (or eliminate) tariffs, quotas and other trade restrictions on items traded between the signatories Interstate reciprocity, recognition of sibling federated states' laws: In the United States specifically: Full Faith and Credit Clause, which provides for it Concealed carry reciprocity Occupational licensing, which in some jurisdictions provides for it Traffic violations reciprocity where non-resident drivers are treated like residents Quid pro quo, a legal concept of the exchange of good or services, each having value
Social sciences and humanities Norm of reciprocity, social norm of in-kind responses to the behavior of others Reciprocity (cultural anthropology), way of defining people's informal exchange of goods and labour Reciprocity (evolution), mechanisms for the evolution of cooperation Reciprocity (international relations), principle that favours, benefits, or penalties that are granted by one state to the citizens or legal entities of another, should be returned in kind Reciprocity (social and political philosophy), concept of reciprocity as in-kind positive or negative responses for the actions of others Reciprocity (social psychology), in-kind positively or negatively connoted responses of individuals towards the actions of others Ethic of reciprocity (the Golden Rule), that one should treat others as one would like others to treat oneself Serial reciprocity, in which the benefactor of a gift or service will in turn provide benefits to a third party
Physical sciences and engineering Reciprocity (engineering), used in the analysis of structures and to resolve complex load conditions Reciprocity (electromagnetism), theorems relating sources and the resulting fields in classical electromagnetism Reciprocity (electrical networks), reciprocity theorem as it relates to current and voltage in electrical networks Reciprocity (network science), measures the tendency of vertex pairs to form mutual connections between each other Reciprocity (optoelectronic), a diode under illumination to the photon emission of the same diode under applied voltage Reciprocity (photography), the relationship between the intensity of the light and duration of the exposure that result in identical exposure Reciprocity of twist and wrench, in screw theory Reciprocity theorem (disambiguation), several unrelated results Reciprocity of antenna transmitting and receiving characteristics Helmholtz reciprocity, linear propagation.
Mathematics Reciprocity law (law of reciprocity) in mathematics, including Quadratic reciprocity, a fundamental result in number theory Cubic reciprocity, theorems that state conditions under which the congruence is solvable Quartic reciprocity, a collection of theorems in elementary and algebraic number theory that state conditions under which the congruence is solvable Artin reciprocity law, a general theorem in number theory that provided a partial solution to Hilbert's ninth problem Reciprocity relation or exact differential, a mathematical differential of the form dQ, for some differentiable function Q Weil reciprocity law Reciprocal polynomials, the coefficients of the remainder polynomial are the bits of the CRC Reciprocal square root Reciprocity (projective geometry), a collineation from a projective space onto its dual space, taking points to hyperplanes (and vice versa) and preserving incidence Frobenius reciprocity, from group representation theory Reciprocity law for Dedekind sums Stanley's reciprocity theorem, states that a certain functional equation is satisfied by the generating function of any rational cone and the generating function of the cone's interior Hermite reciprocity for invariants of binary forms.
Other Reciprocity (Fringe), a 2011 episode of the television series Fringe Rural Municipality of Reciprocity No. 32, Saskatchewan, Canada "Reciprocity", a song by Loudon Wainwright III from his 1976 album T Shirt
See also Reciprocal (disambiguation) Reciprocation (disambiguation) Reciprocity Treaty (disambiguation) Reciprocal altruism between individuals of different species Meeting of the minds in contract law, sometimes called reciprocity Tit for tat