Collaborative Research: Testing the gravitational inverse square law and weak equivalence principle

University Of Washington, Seattle WA

Investigators

Abstract

A primary goal of modern physics is to understand at the most fundamental level possible the nature and behavior of matter and energy. Empirical tests of Einstein's weak-field (Newtonian) gravity play an important role in judging possible extensions of this understanding. Even small deviations from Newtonian behavior could provide new clues to a more general formulation of the so-called Standard Model of fundamental interactions a "holy grail" of modern physics. Such deviations have not yet been detected, but the possibilities for expecting such anomalies at a low level abound in the theoretical literature over the past decade. The goal of this project is to carry out two experiments that will substantially restrict the viability of these theoretical speculations by setting at least an order-of-magnitude more stringent empirical upper limit on the strength of putative non-Newtonian behavior than already established. Alternatively, these more-precise measurements could uncover previously undetected deviations. Either outcome would advance our fundamental understanding of the physical fabric of our universe. This collaboration between research groups at the University of Washington and the University of California Irvine exploits new advances in measurement precision using cryogenic techniques, new methods dramatically to reduce systematic effects, and a unique laboratory facility that provides an ultra-low vibration environment. Moreover, these activities involve young scientists (post-docs, graduate and undergraduate students) as well as corporate partner Boeing Airplane Company and institutional sponsor Pacific Northwest National Laboratory.