Abstract Using the null tetrad approach of Newman and Penrose, the symmetries of the electro-magnetic fields are investigated. It is found that null electromagnetic fields admit Maxwell collineation, and the existence of Ricci collineation and motion is possible only under certain conditions on the spin-coefficients.
Received: 17 October 1994
Accepted manuscript online:
PACS:
04.40.Nr
(Einstein-Maxwell spacetimes, spacetimes with fluids, radiation or classical fields)
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