Speaker
Description
Spin correlations in the Higgs boson decay to four leptons are investigated through detailed studies of kinematic distributions, using matrix element techniques to maximize sensitivity to the tensor structure of the Higgs boson interactions. The analysis, based on data collected by the CMS experiment at the LHC, probes the full decay dynamics, including quantum mechanical interference effects arising from permutations of identical leptons. The polarization density matrix in the H -> ZZ channel is measured, enabling tests of quantum entanglement with implications for violation of a Bell-type inequality. Within this framework, a simultaneous determination of eight Higgs boson couplings to electroweak vector bosons is performed using effective field theory, providing a comprehensive characterization of possible deviations from the Standard Model.