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.
(https://mathworld.wolfram.com/PhaseSpace.html).
(2008-05-02)