<mathematics> The 2n-dimensional space consisting of the possible values of (x1, x1., x2, x2., ..., xn, xn.) for a system of n first-order ordinary differential equations (or more generally, Pfaffian forms).
If n=1, the phase space is known as a phase plane.
http://mathworld.wolfram.com/PhaseSpace.html.
(2008-05-02)
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Nearby terms: Phase Encoded « phase of the moon « phase-shift keying « phase space » phase-wrapping » PHIGS » Philip R. Bagley