Wigner Translations and the Observer Dependence of the Position of Massless Spinning Particles
Abstract
The Wigner little group for massless particles is isomorphic to the Euclidean group SE(2). Applied to momentum eigenstates, or to infinite plane waves, the Euclidean "Wigner translations" act as the identity. We show that when applied to finite wave packets, the translation generators move the packet trajectory parallel to itself through a distance proportional to the particle's helicity. We relate this effect to the spin Hall effect of light and to the Lorentzframe dependence of the position of a massless spinning particle.
 Publication:

Physical Review Letters
 Pub Date:
 May 2015
 DOI:
 10.1103/PhysRevLett.114.210402
 arXiv:
 arXiv:1501.04586
 Bibcode:
 2015PhRvL.114u0402S
 Keywords:

 03.30.+p;
 03.50.De;
 11.30.Cp;
 Special relativity;
 Classical electromagnetism Maxwell equations;
 Lorentz and Poincare invariance;
 High Energy Physics  Theory
 EPrint:
 13 pages, 3 figures. PDFTeX