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Expansion-induced contribution to the precession of binary orbits

Brett Bolen·Luca Bombelli·Raymond Puzio
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Abstract

We point out the existence of new effects of global spacetime expansion on local binary systems. In addition to a possible change of orbital size, there is a contribution to the precession of elliptic orbits, to be added to the well-known general relativistic effect in static spacetimes, and the eccentricity can change. Our model calculations are done using geodesics in a McVittie metric, representing a localized system in an asymptotically Robertson-Walker spacetime; we give a few numerical estimates for that case, and indicate ways in which the model should be improved.

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Brett Bolen, Luca Bombelli, Raymond Puzio. 2001-03-05. Expansion-induced contribution to the precession of binary orbits. https://doi.org/10.1088/0264-9381%2F18%2F7%2F302

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