Mass, zero mass and ... nophysics

R. Saar; S. Groote

doi:10.1007/s00006-017-0758-2

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arXiv · 1606.06966

Mass, zero mass and ... nophysics

R. Saar·S. Groote

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Abstract

In this paper we demonstrate that massless particles cannot be considered as limiting case of massive particles. Instead, the usual symmetry structure based on semisimple groups like $U(1)$, $SU(2)$ and $SU(3)$ has to be replaced by less usual solvable groups like the minimal nonabelian group ${\rm sol}_2$. Starting from the proper orthochronous Lorentz group ${\rm Lor}_{1,3}$ we extend Wigner's little group by an additional generator, obtaining the maximal solvable or Borel subgroup ${\rm Bor}_{1,3}$ which is equivalent to the Kronecker sum of two copies of ${\rm sol}_2$, telling something about the helicity of particle and antiparticle states.

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physics.gen-ph hep-th math-ph math.MP

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R. Saar, S. Groote. 2016-06-16. Mass, zero mass and ... nophysics. https://doi.org/10.1007/s00006-017-0758-2

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