Bell Inequalities and Quantum Correlations in H → ZZ → 2e 2μ

2025/02/05 by Varma, Mira, Baker, Oliver K.
#FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph)

paper · doi:10.48550/arxiv.2502.03219

Abstract

We investigate quantum correlations in Higgs-boson decays (H → ZZ^* → 2e 2μ) using CMS open data at √(s) = 8 TeV, incorporating realistic detector effects. By reconstructing the polarization density matrix of the two-boson system and evaluating the Collins-Gisin-Linden-Massar-Popescu (CGLMP) Bell operator I₃, we quantify entanglement in the ZZ state. Our analysis yields an I₃ value of 2.152 ± 0.003 for signal events (H → ZZ^*), indicating the presence of quantum entanglement. The non-resonant continuum background events (pp → ZZ) yield I₃ = 1.158 ± 0.012, suggesting the absence of quantum correlations. These results demonstrate the feasibility of testing fundamental quantum mechanics at high energy colliders.

Related

• Testing entanglement and Bell inequalities in H → Z Z
• Testing Bell inequalities and entanglement with di-boson final states
• Unfolding quantum entanglement from h→ ZZ^*→ jjℓℓ at a muon collider
• Measurements of Z-boson pair entanglement in decays of Higgs bosons at the ATLAS experiment
• Testing Bell inequalities and probing quantum entanglement at a muon collider