Position and momentum spaces

Physical spaces representing position and momentum, Fourier-transform duals

In physics and geometry, there are two closely related vector spaces, usually three-dimensional but in general of any finite dimension. Position space is the set of all position vectors r in Euclidean space, and has dimensions of length; a position vector defines a point in space. Momentum space is the set of all momentum vectors p a physical system can have; the momentum vector of a particle corresponds to its motion, with units of [mass][length][time]−1.

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