Opposite-sign dilepton asymmetry of neutral B decays: a probe of new physics from CPT or ΔB=ΔQ violation

We show that new physics, either from CPT violation in B0–B̄0 mixing or from ΔB=−ΔQ transitions, may lead to an opposite-sign dilepton asymmetry of neutral B-meson decays. Both effects have the same time-dependent behavior and therefore are in general indistinguishable from each other. We also clarify some ambiguity associated with the constraint on CPT violation in semileptonic decays of incoherent B0 and B̄0 mesons.