Theoretical simulation demonstrates CHSH violations in postselected entangled states using a local sigmoid threshold, highlighting how detection loopholes mimic quantum correlations.
Key Points
To determine whether a local hidden-variable model using a sigmoid threshold mechanism can reproduce quantum-like correlations in postselected Bell-type measurements on entangled two-qubit states.
Simulated linear polarization measurements on nonmaximally entangled two-qubit states (|Phi_r> and |Psi_r>) using a setting-dependent sigmoid threshold mechanism that violates fair-sampling assumptions.
Evaluated correlation metrics under CHSH-type configurations and calculated the CH-Eberhard J parameter in a one-detector-per-side layout across various entanglement parameters.
Implemented an extended local adaptive-threshold model featuring one-sided memory to evaluate shifts in detection statistics.
Produced apparent CHSH-type violations strictly within the postselected detected sample via setting-dependent detection, bypassing Mermin's 82.8% efficiency bound without conflicting with loophole-free Bell tests.
Maintained strictly negative CH-Eberhard values (J < 0) across all tested entanglement parameters, preserving local realism for the full ensemble.
Demonstrated that a local one-sided memory mechanism induces a systematic, reproducible numerical shift in J while keeping the overall CH-Eberhard local validity intact.