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Quantum discord and steering in top quarks at the LHC

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arxiv 2209.03969 v2 pith:S3GDUPYZ submitted 2022-09-08 quant-ph hep-exhep-phhep-th

Quantum discord and steering in top quarks at the LHC

classification quant-ph hep-exhep-phhep-th
keywords quantumdiscordsteeringquarksentanglementnatureasymmetricavailable
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
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Top quarks have been recently shown to be a promising system to study quantum information at the highest-energy scale available. The current lines of research mostly discuss topics such as entanglement, Bell nonlocality or quantum tomography. Here, we provide the full picture of quantum correlations in top quarks by studying also quantum discord and steering. We find that both phenomena are present at the LHC. In particular, quantum discord in a separable quantum state is expected to be detected with high-statistical significance. Interestingly, due to the singular nature of the measurement process, quantum discord can be measured following its original definition, and the steering ellipsoid can be experimentally reconstructed, both highly-demanding measurements in conventional setups. In contrast to entanglement, the asymmetric nature of quantum discord and steering can provide witnesses of $CP$-violating physics beyond the Standard Model.

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