THE HELICITY OF THE FREE ELECTROMAGNETIC-FIELD AND ITS PHYSICAL MEANING

Authors
AFANASIEV GN STEPANOVSKY YP
Citation
Gn. Afanasiev et Yp. Stepanovsky, THE HELICITY OF THE FREE ELECTROMAGNETIC-FIELD AND ITS PHYSICAL MEANING, Nuovo cimento della Società Italiana di Fisica. A. Nuclei, particles and fields, 109(3), 1996, pp. 271-279
Citations number
26
Categorie Soggetti
Physics, Particles & Fields
Journal title
Nuovo cimento della Società Italiana di Fisica. A. Nuclei, particles and fields → ACNP
ISSN journal
11241861
Volume
109
Issue
3
Year of publication
1996
Pages
271 - 279
Database
ISI
SICI code
1124-1861(1996)109:3<271:THOTFE>2.0.ZU;2-0
Abstract
The notion of helicity for the free electromagnetic field is analysed. The generalized helicity is introduced which is a conserved quantity coinciding with the difference of the right and left circularly polari zed photons composing the electromagnetic field. It seems that it comp letes the list of the zilch-type invariants found by Lipkin and Ragusa . The gauge-invariant expression for the energy of the free gravitatio nal field is obtained which strongly resembles the well-known bilinear expression for the total number of photons composing the electromagne tic field.