An Introduction to the Quantum Backflow Effect

@inproceedings{JMYearsley2013AnIT,
  title={An Introduction to the Quantum Backflow Effect},
  author={J.M.Yearsley and J.J.Halliwell},
  year={2013}
}
We present an introduction to the backflow effect in quantum mechanics – the phenomenon in which a state consisting entirely of positive momenta may have negative current and the probability flows in the opposite direction to the momentum. We show that the effect is present even for simple states consisting of superpositions of gaussian wave packets, although the size of the effect is small. Inspired by the numerical results of Penz et al, we present a wave function whose current at any time… 

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