Uninformed Bayesian quantum thermometry

  title={Uninformed Bayesian quantum thermometry},
  author={Julia Boeyens and Stella Seah and Stefan Nimmrichter},
  journal={Physical Review A},
We study the Bayesian approach to thermometry with no prior knowledge about the expected temperature scale, through the example of energy measurements on fully or partially thermalized qubit probes. We show that the most common Bayesian estimators, namely the mean and the median, lead to high-temperature divergences when used for uninformed thermometry. To circumvent this and achieve better overall accuracy, we propose two new estimators based on an optimization of relative deviations. Their… 

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