# Is an electron technically a set of two particles?

The electron - described as a four-spinor in the Dirac equation - transforms according to the $(1/2,0)\oplus(0,1/2)$ representation of the Lorentz group, so it is actually a direct sum of a left- and right-handed Weyl spinor. So is the electron technically a set of two other massless fundamental particles?

• I would just repeat my answer for the photon here, except adding that the Weyl degrees of freedom in a Dirac spinor do not decouple if the spinor is massive. Feb 18, 2015 at 15:57
• Haha.. Are you going to ask that for every particle? Feb 18, 2015 at 16:02
• @both: Well actually I honestly thought these two questions are rather unrelated. The Dirac spinor really is the direct sum of two Weyl spinors, but can the same be said of the photon? Is it the direct sum of two helicity representations? And furthermore: does this type of "doubling" (fundamental particle arises as grouping together of two technically/mathematically even more fundamental entities) occur for any particle so that I could indeed ask the same question for every SM particle? Feb 18, 2015 at 16:14