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arXiv · 1108.2547

New experimental limits on non-Newtonian forces in the micrometer-range

A. O. Sushkov·W. J. Kim·D. A. R. Dalvit·S. K. Lamoreaux
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Abstract

We report measurements of the short-range forces between two macroscopic gold-coated plates using a torsion pendulum. The force is measured for separations between 0.7 $μ$m and 7 $μ$m, and is well described by a combination of the Casimir force, including the finite-temperature correction, and an electrostatic force due to patch potentials on the plate surfaces. We use our data to place constraints on the Yukawa-type "new" forces predicted by theories with extra dimensions. We establish a new best bound for force ranges 0.4 $μ$m to 4 $μ$m, and, for forces mediated by gauge bosons propagating in $(4+n)$ dimensions and coupling to the baryon number, extract a $(4+n)$-dimensional Planck scale lower limit of $M_*>70$ TeV.

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A. O. Sushkov, W. J. Kim, D. A. R. Dalvit, S. K. Lamoreaux. 2011-08-12. New experimental limits on non-Newtonian forces in the micrometer-range. https://doi.org/10.1103/physrevlett.107.171101

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