Behavior of the maximum likelihood in quantum state tomography

  title={Behavior of the maximum likelihood in quantum state tomography},
  author={Travis L. Scholten and Robin Blume-Kohout},
  journal={New Journal of Physics},
Quantum state tomography on a d-dimensional system demands resources that grow rapidly with d. They may be reduced by using model selection to tailor the number of parameters in the model (i.e., the size of the density matrix). Most model selection methods typically rely on a test statistic and a null theory that describes its behavior when two models are equally good. Here, we consider the loglikelihood ratio. Because of the positivity constraint ρ ≥ 0, quantum state space does not generally… 

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