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A search for a composition-dependent gravitational force
Abstract
The weak equivalence principle (WEP) maintains that all objects in a uniform gravitational field fall at the same rate, and this rate is independent of composition. I have used the Northfield Mountain Pumped Storage Reservoir as a modulated source of gravitational mass and measured the acceleration of copper and polyethylene test masses towards the reservoir with a sensitive torsion pendulum. The geometry of the pendulum is such that any differential acceleration would manifest itself as a shift in the pendulum period. Therefore, the signature of a WEP--violating force would be a period shift that correlates with the rise and fall of the mass in the Northfield Mountain reservoir. I have looked for such a correlation and find that if there is a difference in the accelerations of copper and polyethylene toward the water in the reservoir, it is less that 6.0 $\times$ 10$\sp{-9}$cm/s. We report the limits this places on the possible coupling strength of a possible composition dependent fifth force.
Subject Area
Physics
Recommended Citation
Nakroshis, Paul Andrew, "A search for a composition-dependent gravitational force" (1994). Doctoral Dissertations Available from Proquest. AAI9420667.
https://scholarworks.umass.edu/dissertations/AAI9420667