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arXiv · 2203.02627

Approximating projections by quantum operations

Roy Araiza·Colton Griffin·Aneesh Khilnani·Thomas Sinclair
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Abstract

Using techniques from semidefinite programming, we study the problem of finding a closest quantum channel to the projection onto a matricial subsystem. We derive two invariants of matricial subsystems which are related to the quantum Lov\'asz theta function of Duan, Severini, and Winter.

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Roy Araiza, Colton Griffin, Aneesh Khilnani, Thomas Sinclair. 2022-03-05. Approximating projections by quantum operations. https://doi.org/10.1016/j.laa.2023.01.008

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