Bilocal

Bilocal is an adjective used to describe something that involves, concerns, or is located at two distinct locations or points. The prefix bi- means two, and local derives from location or locality, so the term emphasizes dual-site scope or two-point dependence. It is used across multiple disciplines to convey a two-point or two-site character.

In physics and mathematics, bilocal concepts often refer to objects defined on pairs of spacetime points rather than a single point. A bilocal field, for example, is a function that depends on two coordinates x and y, rather than only one. Such constructs appear in certain nonperturbative approaches to quantum field theory and are employed to model extended bound states or to reformulate problem sets in which correlations between two points are important. In these contexts, bilocal descriptions can complement or simplify single-point formulations by capturing relative and center-of-mass degrees of freedom jointly.

In quantum information and foundations of quantum mechanics, bilocality denotes a network scenario with two independent sources distributing subsystems to multiple parties. This leads to correlations that may violate classical or local constraints under specific independence assumptions. Bilocality has generated specialized inequalities and analytical frameworks for testing nonlocality in networked experiments, distinguishing genuine network effects from standard Bell-type scenarios.

In general use, bilocal conveys a two-point or two-site emphasis and is most common in technical discussions where two-location structure matters.