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arXiv · 0806.3101

Pure-state quantum trajectories for general non-Markovian systems do not exist

Howard M. Wiseman·J. M. Gambetta
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Abstract

Since the first derivation of non-Markovian stochastic Schrödinger equations, their interpretation has been contentious. In a recent Letter [Phys. Rev. Lett. 100, 080401 (2008)], Diósi claimed to prove that they generate "true single system trajectories [conditioned on] continuous measurement". In this Letter we show that his proof is fundamentally flawed: the solution to his non-Markovian stochastic Schrödinger equation at any particular time can be interpreted as a conditioned state, but joining up these solutions as a trajectory creates a fiction.

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Howard M. Wiseman, J. M. Gambetta. 2008-09-30. Pure-state quantum trajectories for general non-Markovian systems do not exist. https://doi.org/10.1103/physrevlett.101.140401

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