A free particle moving in one dimension is in the initial state ψ(x,0). Prove that
<p> is constant in time by direct calculation (i.e., without recourse to the
commutator theorem regarding constants of the motion).
<p> = m*(d<x>/dt) ?
The Attempt at a Solution
I am not really sure where to start... Should I find <x> ? is that the easiest way? And how do you this for a free particle ? stuff is confusing me. Can someone give me a start here...