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A model of CPT violation for neutrinos

G. Barenboim·J. Lykken
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Abstract

Any local relativistic quantum field theory of Dirac-Weyl fermions conserves CPT. Here we examine whether a simple nonlocal field theory can violate CPT. We construct a new relativistic field theory of fermions, which we call ``homeotic'', which is nonlocal but causal and Lorentz invariant. The free homeotic theory is in fact equivalent to free Dirac theory. We show that a homeotic theory with a suitable nonlocal four-fermion interaction is causal and as a result has a well-defined perturbative S-matrix. By coupling a right-handed homeotic fermion to a left-handed Dirac-Weyl fermion, we obtain a causal theory of CPT-violating neutrino oscillations.

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G. Barenboim, J. Lykken. 2002-10-29. A model of CPT violation for neutrinos. https://doi.org/10.1016/s0370-2693(02)03262-8

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