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arXiv · 0903.4772

Comment on recent papers regarding next-to-leading order spin-spin effects in gravitational interaction

Jan Steinhoff·Gerhard Schäfer
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Abstract

It is argued that the tetrad in a recent paper by Porto and Rothstein on gravitational spin-spin coupling should not have the given form. The fixation of that tetrad was suggested by Steinhoff, Hergt, and Schaefer as a possible source for the disagreement found in the spin-squared dynamics. However, this inconsistency will only show up in the next-to-leading order spin-orbit dynamics and not in the spin-squared dynamics. Instead, the disagreement found at the next-to-leading order spin-squared level is due to a sign typo in the spin-squared paper by Porto and Rothstein.

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Jan Steinhoff, Gerhard Schäfer. 2009-10-31. Comment on recent papers regarding next-to-leading order spin-spin effects in gravitational interaction. https://doi.org/10.1103/physrevd.80.088501

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