The term “phase” appears in different contexts:
the complex phase of a complex number $c$ is the real number $\phi$ in the decomposition $c = {\vert c \vert} e^{i \phi}$;
the phase of a wave function in physics is just this complex phase, the wave function being (locally) a function with values in the complex numbers;
correspondingly then the phase difference between two linearly dependent vectors of a complex Hilbert space is the phase of the complex number that relates them;
in thermodynamics and statistical physics different phases of a physical system label different order parameters that distinguish macroscopically different regions of the configuration space of the system;
the phase space of a physical system is its space of classical solutions, typically given coordinates involving generalised momenta (for a relation of this to the phase of a wave function above see at phase and phase space in physics).
Last revised on March 22, 2013 at 18:13:31. See the history of this page for a list of all contributions to it.