Role of Post-Selection in Two-Photon Interferometer Tests of Bell's Inequality

TL;DR

This paper examines the role of post-selection in two-photon Bell tests, demonstrating that certain local models can mimic quantum correlations but are not fully realistic, highlighting the importance of post-selection in interpreting experimental results.

Contribution

It clarifies the limitations of a recent local model for two-photon Bell tests and discusses how post-selection influences the interpretation of experimental violations.

Findings

The model by Cabello et al. is local but not realistic.

Post-selection plays a crucial role in the interpretation of two-photon Bell tests.

Certain local models can reproduce some experimental outcomes but lack full realism.

Abstract

Experimental tests of Bell's inequality based on two-photon interferometry consider only those coincidence events in which both photons arrive at the detectors at the same time. In a recent paper, Cabello et al. [Phys. Rev. Lett. 102, 040401 (2009)] proposed a local model that is consistent with some aspects of these experiments. It is shown here that the model proposed by Cabello et al. is local but not realistic, and the role of post-selection in experiments of this kind is discussed.