Revisiting quantum mechanics on non-commutative space–time

Abstract We construct an effective commutative Schrodinger equation in Moyal space–time in ( 1 + 1 ) -dimension where both t and x are operator-valued and satisfy t ˆ , x ˆ = i θ . Beginning with a time-reparametrised invariant form of an action we identify the actions of various space–time coordinates and their conjugate momenta on quantum states, represented by Hilbert–Schmidt operators. Since time is also regarded as a configuration space variable, we show how an ‘induced’ inner product can be extracted, so that an appropriate probabilistic interpretation is obtained. We then discuss several other applications of the formalism developed so far.