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arXiv · 2602.02815

An Improved Torsion Balance Test of the Equivalence Principle Towards the Sun

M. P. Ross·E. A. Shaw·C. Gettings·S. K. Apple·I. A. Paulson·J. H. Gundlach
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Abstract

We search for violations of the Equivalence Principle towards the Sun using a rotating torsion balance apparatus. We set 95\%-confidence limits on violations with beryllium and aluminum test bodies of $η_{\odot, Be-Al} \leq 2.1 \times 10^{-13}$. These results are a factor of four improvement of previously reported results towards the Sun and a $\sim20\%$ improvement on previous torsion balance tests regardless of source.

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M. P. Ross, E. A. Shaw, C. Gettings, S. K. Apple, I. A. Paulson, J. H. Gundlach. 2026-02-02. An Improved Torsion Balance Test of the Equivalence Principle Towards the Sun. https://arxiv.org/abs/2602.02815

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