Arrival Times, Complex Potentials and Decoherent Histories

Details Arrival Times, Complex Potentials and Decoherent Histories Arrival Times, Complex Potentials and Decoherent Histories

2009-03-11

arxiv.org/abs/0903.1957v1

Physics Review A 79(6): 062101 (2009)

Physics

Quantum Physics

43 pages

Scientific paper

We address a number of aspects of the arrival time problem defined using a complex potential of step function form. We concentrate on the limit of a weak potential, in which the resulting arrival time distribution function is closely related to the quantum-mechanical current. We first consider the analagous classical arrival time problem involving an absorbing potential, and this sheds some light on certain aspects of the quantum case. In the quantum case, we review the path decomposition expansion (PDX), in which the propagator is factored across a surface of constant time, so is very useful for potentials of step function form. We use the PDX to derive the usual scattering wave functions and the arrival time distribution function. This method gives a direct and geometrically appealing account of known results (but also points the way to how they can be extended to more general complex potentials). We use these results to carry out a decoherent histories analysis of the arrival time problem, taking advantage of a recently demonstrated connection between pulsed measurements and complex potentials. We obtain very simple and plausible expressions for the class operators (describing the amplitudes for crossing the origin during intervals of time) and show that decoherence of histories is obtained for a wide class of initial states (such as simple wave packets and superpositions of wave packets). We find that the decoherent histories approach gives results with a sensible classical limit that are fully compatible with standard results on the arrival time problem. We also find some interesting connections between backflow and decoherence.

Affiliated with

Also associated with

No associations

Rating

Arrival Times, Complex Potentials and Decoherent Histories does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Arrival Times, Complex Potentials and Decoherent Histories, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Arrival Times, Complex Potentials and Decoherent Histories will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-123794