A quantum-information theoretic analysis of three-flavor neutrino oscillations: Quantum entanglement, nonlocal and nonclassical features of neutrinos

Histories of Neutrino Oscillation of Consistency Induced by the Presence of Normal Matter

Oscillation of two-flavour neutrinos is considered within a quantum mechanical framework of consistent (decoherent) dynamic histories. We investigate how consistency of selected three-time histories is affected by oscillation parameters. We show that the presence of normal matter is crucial to maintain consistency of certain classes of neutrinos’ dynamic histories and that the consistency does not depend on a Majorana phase and remains insensitive to a potential CP violation.

Testing Bell Inequalities at the LHC with Top-Quark Pairs

Correlations between the spins of top-quark pairs produced at a collider can be used to probe quantum entanglement at energies never explored so far. We show how the measurement of a single observable can provide a test of the violation of a Bell inequality at the 98% C.L. with the statistical uncertainty of the data already collected at the Large Hadron Collider, and at the 99.99% C.L. with the higher luminosity of the next run. Detector acceptance, efficiency, and migration effects are taken into account. The test relies on the spin correlations alone and does not require the determination of probabilities-in contrast to all other tests of Bell inequalities.

Neutrino Oscillations in the Presence of Matter and Continuous Non-Selective Measurement

We investigate three-flavor neutrino oscillation affected by an environment mimicking a continuous non-selective measurement. We show that such a coupling that is given by a measured observable affects probability of inter-flavor neutrino transition and a steady-state correlation function of the neutrino’s flavor. We juxtapose and compare our predictions influenced by matter’s scattering and CP-violation.

Violation of the Leggett-Garg Inequality in Neutrino Oscillations

The Leggett-Garg inequality, an analogue of Bell's inequality involving correlations of measurements on a system at different times, stands as one of the hallmark tests of quantum mechanics against classical predictions. The phenomenon of neutrino oscillations should adhere to quantum-mechanical predictions and provide an observable violation of the Leggett-Garg inequality. We demonstrate how oscillation phenomena can be used to test for violations of the classical bound by performing measurements on an ensemble of neutrinos at distinct energies, as opposed to a single neutrino at distinct times. A study of the MINOS experiment's data shows a greater than 6σ violation over a distance of 735 km, representing the longest distance over which either the Leggett-Garg inequality or Bell's inequality has been tested.