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A model-independent test of spatial variations of the Newtonian gravitational constant in some extrasolar planetary systems

Lorenzo Iorio
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Abstract

In this paper we directly constrain possible spatial variations of the Newtonian gravitational constant G over ranges 0.01-5 AU in various extrasolar multi-planet systems. By means of the third Kepler's law we determine the quantity Γ_ XY=G_X/G_Y for each couple of planets X and Y located at different distances from their parent star: deviations of the measured values of Γfrom unity would signal variations of G. The obtained results for η=1-Γare found to be well compatible with zero within the experimental errors (η/δη= 0.2-0.3). A comparison with an analogous test previously performed in our Solar System is made.

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BibTeXRIS

Lorenzo Iorio. 2013-10-08. A model-independent test of spatial variations of the Newtonian gravitational constant in some extrasolar planetary systems. https://doi.org/10.1111/j.1365-2966.2007.11542.x

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