Quantum Field Theory of Particle Oscillations: Neutron-Antineutron Conversion

Understand

We formulate the quantum field theory description of neutron-antineutron oscillations in the framework of canonical quantization, in analogy with the Bardeen--Cooper--Schrieffer (BCS) theory and the Nambu--Jona-Lasinio model.

• The physical vacuum of the theory is a condensate of pairs of {\it would-be neutrons and antineutrons} in the absence of the baryon-number violating interaction.
• The quantization procedure defines uniquely the mixing of massive Bogoliubov quasiparticle states which represent the neutron.
• In spite of not being mass eigenstates, neutron and antineutron states are defined on the physical vacuum and the oscillation formulated in asymptotic states.