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arXiv · gr-qc/0110078

Real null coframes in general relativity and GPS type coordinates

M. Blagojevic·J. Garecki·F. W. Hehl·Yu. N. Obukhov
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Abstract

Based on work of Derrick, Coll, and Morales, we define a `symmetric' null coframe with {\it four real null covectors}. We show that this coframe is closely related to the GPS type coordinates recently introduced by Rovelli.

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M. Blagojevic, J. Garecki, F. W. Hehl, Yu. N. Obukhov. 2001-11-28. Real null coframes in general relativity and GPS type coordinates. https://doi.org/10.1103/physrevd.65.044018

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