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On the existence of physical transformations between sets of quantum states

Anthony Chefles·Richard Jozsa·Andreas Winter
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Abstract

Let A = {rho_1,...,rho_n} be a given set of quantum states. We consider the problem of finding necessary and sufficient conditions on another set B = {sigma_1,...,sigma_n} that guarantee the existence of a physical transformation taking rho_i to sigma_i for all i. Uhlmann has given an elegant such condition when both sets comprise pure states. We give a simple proof of this condition and develop some consequences. Then we consider multi-probabilistic transformations between sets of pure states which leads to conditions for the problem of transformability between A and B when one set is pure and the other is arbitrary.

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Anthony Chefles, Richard Jozsa, Andreas Winter. 2003-07-30. On the existence of physical transformations between sets of quantum states. https://doi.org/10.1142/s0219749904000031

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