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Massive neutrinos, massless neutrinos, and so(4,2)invariance

A. J. Bracken
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Abstract

Dirac's equation for a massless particle is conformal invariant, and accordingly has an so(4,2)invariance algebra. It is known that although Dirac's equation for a massive spin 1/2 particle is not conformal invariant, it too has an so(4,2) invariance algebra. It is shown here that the algebra of operators associated with a 4-component massless particle, or two flavors of 2-component massless particles, can be deformed into the algebra of operators associated with a spin 1/2 particle with positive rest mass. It is speculated that this may be exploited to describe massless neutrino mixing.

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A. J. Bracken. 2005-04-12. Massive neutrinos, massless neutrinos, and so(4,2)invariance. https://arxiv.org/abs/hep-th/0504111

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