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arXiv · 2006.14247

A quantum reference frame size-accuracy trade-off for quantum channels

Takayuki Miyadera·Leon Loveridge
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Abstract

The imposition of symmetry upon the nature and structure of quantum observables has recently been extensively studied, with quantum reference frames playing a crucial role. In this paper, we extend this work to quantum transformations, giving quantitative results showing, in direct analogy to the case of observables, that a "large" reference frame is required for non-covariant channels to be well approximated by covariant ones. We apply our findings to the concrete setting of SU(2) symmetry.

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Takayuki Miyadera, Leon Loveridge. 2020-06-25. A quantum reference frame size-accuracy trade-off for quantum channels. https://doi.org/10.1088/1742-6596/1638/1/012008

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