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On the Physical Meaning of the Robinson-Trautman-Maxwell Fields

Carlos Kozameh·E. T. Newman·Gilberto Silva-Ortigoza
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Abstract

We study the Robinson-Trautman-Maxwell Fields in two closely related coordinate systems, the original Robinson-Trautman (RT) coordinates (in a more general context, often referred to as NU coordinates) and Bondi coordinates. In particular, we identify one of the RT variables as a velocity and then from the Bondi energy-momentum 4-vector, we find kinematic expressions for the mass and momentum in terms of this velocity. From these kinematic expressions and the energy-momentum loss equation we obtain surprising equations of motion for `the center of mass' of the source where the motion takes place in the four-dimensional Poincare translation sub-group of the BMS group.

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Carlos Kozameh, E. T. Newman, Gilberto Silva-Ortigoza. 2006-07-19. On the Physical Meaning of the Robinson-Trautman-Maxwell Fields. https://doi.org/10.1088/0264-9381%2F23%2F23%2F002

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