Avoiding loopholes with hybrid Bell-Leggett-Garg inequalities

Justin Dressel, Alexander N. Korotkov
2014 Physical Review A. Atomic, Molecular, and Optical Physics  
By combining the postulates of macrorealism with Bell locality, we derive a qualitatively different hybrid inequality that avoids two loopholes that commonly appear in Leggett-Garg and Bell inequalities. First, locally invasive measurements can be used, which avoids the "clumsiness" Leggett-Garg inequality loophole. Second, a single experimental ensemble with fixed analyzer settings is sampled, which avoids the "disjoint sampling" Bell inequality loophole. The derived hybrid inequality has the
more » ... ame form as the Clauser-Horne-Shimony-Holt Bell inequality; however, its quantum violation intriguingly requires weak measurements. A realistic explanation of an observed violation requires either the failure of Bell locality, or a preparation-conspiracy of finely tuned and nonlocally correlated noise. Modern superconducting and optical systems are poised to implement this test.
doi:10.1103/physreva.89.012125 fatcat:vburoicupjdorbj6h5npj6wvia