Canonical commutation relation 对易关系
（重定向自Commutation relations）
In quantum mechanics (physics), the canonical commutation relation is the fundamental relation between canonical conjugate quantities (quantities which are related by definition such that one is the Fourier transform of another). For example,
between the position operator x and momentum operator px in the x direction of a point particle in one dimension, where [x , px] = x px − px x is the commutator of x and px , i is the imaginary unit, and ℏ is the reduced Planck's constant h/2π . In general, position and momentum are vectors of operators and their commutation relation between different components of position and momentum can be expressed as