Dynamical maps and measurements

Aik-meng Kuah; E. C. G. Sudarshan

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arXiv · quant-ph/0209083

Dynamical maps and measurements

Aik-meng Kuah·E. C. G. Sudarshan

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Abstract

We show how a set of POVMs, expressed as a set of $μ$ linear maps, can be performed with a unitary transformation followed by a von-Neumann measurement with an ancillary system of no more than $μN^2$ dimensions. This result shows that all generalized linear transformations and measurements on density matrices can be performed by unitary transformations and von-Neumann measurements by coupling a suitably large ancillary system.

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Aik-meng Kuah, E. C. G. Sudarshan. 2002-09-13. Dynamical maps and measurements. https://arxiv.org/abs/quant-ph/0209083

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