Entanglement and Bell inequalities violation in $H\to ZZ$ with anomalous coupling

Abstract

We discuss entanglement and violation of Bell-type inequalities for a system of two $Z$ bosons produced in Higgs decays. We take into account beyond the Standard Model (anomalous) coupling between $H$ and daughter bosons but we limit ourselves to an overall scalar $ZZ$ state (we exclude the possibility that $H$ contains a pseudo-scalar component). In particular we consider the case when each $Z$ decays further into fermion-antifermion pair. We find that a $ZZ$ state is entangled and violates the CGLMP inequality for all values of the (anomalous) coupling constant.