Update: Parallel-Plate Null Test of the Gravitational Inverse Square Law

ORAL

Abstract

Gravity has not been experimentally observed at scales smaller than the diameter of human hair, barely smaller than the dark energy length-scale of 85 microns. Our sensitive ($10^{-14}$ N-m/$\sqrt{\mbox{Hz}}$) torsion balance uses a parallel-plate mass configuration to maximize signal and to create a Gauss's Law null-test of short range gravity. Our first science run is complete, and final analysis is underway. The measurement's sensitivity is expected to be comparable to the existing best limits at $\sim56$ microns, but with different leading sources of systematic uncertainty. Sensitivity upgrades are now straightforward, and will commence when our initial results are final. The talk will discuss important systematic effects and analysis challenges inherent to parallel-plate measurements of short-distance forces.

*Supported by NSF (PHY0969199, PHY0700912, and PHY0653863) and by DOE support for CENPA

Authors

  • Charles Hagedorn

    • University of Washington / CENPA
  • Stephan Schlamminger

    • NIST / University of Washington
    • NIST
  • Matthew Turner

    • University of Washington / CENPA
  • Krishna Venkateswara

    • University of Washington / CENPA
  • Jens Gundlach

    • University of Washington / CENPA