A New Apparatus for Detecting Micron-Scale Deviations from Newtonian Gravity

TL;DR

This paper introduces a novel experimental setup using micromachined masses and cantilever detection to measure potential deviations from Newtonian gravity at micron scales, achieving sensitivity comparable to current best limits.

Contribution

The paper presents a new apparatus design with rotary mass actuation and cantilever-based force detection for short-range gravity tests, demonstrating its capability to constrain non-Newtonian effects.

Findings

Sensitivity matches best existing limits at 5 microns

No non-Newtonian effects detected at current sensitivity

First data demonstrating the apparatus's potential

Abstract

We describe the design and construction of a new apparatus for detecting or constraining deviations from Newtonian gravity at short length scales. The apparatus consists of a new type of probe with rotary mass actuation and cantilever-based force detection which is used to directly measure the force between two micromachined masses separated by tens of microns. We present the first data from the experiment, and discuss the prospects of more precisely constraining or detecting non-Newtonian effects using this probe. Currently, the sensitivity to attractive mass-dependent forces is equal to the best existing limits at length scales near 5 microns. No non-Newtonian effects are detected at that level.