Article

Torsion-balance tests of the weak equivalence principle

Classical and Quantum Gravity (Impact Factor: 3.56). 07/2012; 29(18). DOI: 10.1088/0264-9381/29/18/184002
Source: arXiv

ABSTRACT We briefly summarize motivations for testing the weak equivalence principle
and then review recent torsion-balance results that compare the differential
accelerations of beryllium-aluminum and beryllium-titanium test body pairs with
precisions at the part in $10^{13}$ level. We discuss some implications of
these results for the gravitational properties of antimatter and dark matter,
and speculate about the prospects for further improvements in experimental
sensitivity.

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