Novel Tests of Gravity Below Fifty Microns

POSTER

Abstract

Attempts to unify the Standard Model and General Relativity often include features that violate the Weak Equivalence Principle (WEP) and/or the gravitational Inverse-Square Law (ISL). A violation of these would question our fundamental understanding of gravity. To further understand nature, undergraduate researchers and faculty at Cal Poly Humboldt are using an experiment to measure gravitational interactions below 50 microns. The experiment uses a torsion pendulum with equal masses of two different materials arranged as a composition dipole. The twist of the torsion pendulum is measured as an attractor mass in a parallel-plate configuration is oscillated nearby. This creates a time dependent torque on the pendulum. The magnitude and size of this torque may lead to deviations in the WEP or ISL at this untested scale. Several improvements to the apparatus have recently been designed and implemeted, the results are the ability to test at levels the experiment was previously unable to test.

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Presenters

  • Abby Keltz

    California State Polytechnic University, Humboldt

Authors

  • Abby Keltz

    California State Polytechnic University, Humboldt

  • C. D. Hoyle

    Cal Poly Humboldt, California Polytechnic University, Humboldt

  • Evan Rosales

    Cal Poly Humboldt, California Polytechnic University, Humboldt

  • Kelsey Sako

    Cal Poly Humboldt

  • Frederick X Kuster-Tabares

    Cal Poly Humboldt, California State Polytechnic University, Humboldt