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Updated: Mar 19, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Stronger Limits on Hypothetical Yukawa Interactions in the 30-8000 nm Range
Y-J Chen1,2, W K Tham1, D E Krause3,4
1Department of Physics, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, USA.
Abstract:
We report the results of new differential force measurements between a test mass and rotating source masses of gold and silicon to search for forces beyond Newtonian gravity at short separations. The technique employed subtracts the otherwise dominant Casimir force at the outset and, when combined with a lock-in amplification technique, leads to a significant improvement (up to a factor of 10^{3}) over existing limits on the strength (relative to gravity) of a putative force in the 40-8000 nm interaction range.
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