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Quantum tops at the LHC: from entanglement to Bell inequalities

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arxiv 2110.10112 v2 pith:OB7MJXSK submitted 2021-10-19 hep-ph hep-exquant-ph

Quantum tops at the LHC: from entanglement to Bell inequalities

classification hep-ph hep-exquant-ph
keywords bellinequalitiesentanglementeventshighquantumsensitiveviolation
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
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We present the prospects of detecting quantum entanglement and the violation of Bell inequalities in $t\bar{t}$ events at the LHC. We introduce a unique set of observables suitable for both measurements, and then perform the corresponding analyses using simulated events in the dilepton final state, reconstructing up to the unfolded level. We find that entanglement can be established at better than 5$\sigma$ both at threshold as well as at high $p_T$ already in the LHC Run 2 dataset. On the other hand, only very high-$p_T$ events are sensitive to a violation of Bell inequalities, making it significantly harder to observe experimentally. By employing a sensitive and robust observable, two different unfolding methods and independent statistical approaches, we conclude that, at variance with previous estimates, testing Bell inequalities will be challenging even in the high luminosity LHC run.

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Forward citations

Cited by 28 Pith papers

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