Discrete dynamics in the set of quantum measurements
- URL: http://arxiv.org/abs/2308.05835v1
- Date: Thu, 10 Aug 2023 19:34:04 GMT
- Title: Discrete dynamics in the set of quantum measurements
- Authors: Albert Rico and Karol \.Zyczkowski
- Abstract summary: A quantum measurement, often referred to as positive operator-valued measurement (POVM), is a set of positive operators $P_i=P_idaggeq 0$ summing to identity.
We analyze dynamics induced by blockwise bistochastic matrices, in which both columns and rows sum to the identity.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: A quantum measurement, often referred to as positive operator-valued
measurement (POVM), is a set of positive operators $P_i=P_i^\dag\geq 0$ summing
to identity, $\sum_iP_i=1\!\!1$. This can be seen as a generalization of a
probability distribution of positive real numbers summing to unity, whose
evolution is given by a stochastic matrix. From this perspective, we consider
transformations of quantum measurements induced by blockwise stochastic
matrices, in which each column defines a POVM. These transformations can be
simulated with a sequence of two conditional measurements, and their input and
output are always jointly measurable. Analyzing dynamics induced by blockwise
bistochastic matrices, in which both columns and rows sum to the identity, we
formulate an operator majorization relation between quantum measurements, which
allows to establish a resource theory in the set of quantum measurements.
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