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Internal Space-time Symmetries of Massless Particles and Neutrino Polarization as a Consequence of Gauge Invariance

Y. S. Kim
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Abstract

There are gauge-transformation operators applicable to massless spin-1/2 particles within the little-group framework of internal space-time symmetries of massive and massless particles. It is shown that two of the $SL(2,c)$ spinors are invariant under gauge transformations while the remaining two are not. The Dirac equation contains only the gauge-invariant spinors leading to polarized neutrinos. It is shown that the gauge-dependent $SL(2,c)$ spinor is the origin of the gauge dependence of electromagnetic four-potentials. It is noted also that, for spin-1/2 particles, the symmetry group for massless particles is an infinite-momentum/zero-mass limit of the symmetry group for massive particles.

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Y. S. Kim. 2002-01-31. Internal Space-time Symmetries of Massless Particles and Neutrino Polarization as a Consequence of Gauge Invariance. https://arxiv.org/abs/hep-th/0201262

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