DC Cancellation As a Method of Generating a t^2 Response and of Solving the Radial Nonobservability Problem in a Concentric Free-Falling Two-Sphere Equivalence-Principle Experiment in a Drag-Free Satellite

TL;DR

This paper introduces a novel DC cancellation method that addresses key measurement challenges in free-fall Equivalence-Principle experiments in satellites, enabling long-duration t^2 responses and improved observability of EP violations.

Contribution

The paper presents a new cancellation technique that suppresses nonobservability issues and produces sustained t^2 responses, advancing satellite-based EP testing capabilities.

Findings

Suppressed semimajor-axis error indistinguishable from EP violation

Generated t^2 response lasting up to 10^6 seconds

Achieved measurement sensitivity comparable to a 0.1-10 AU drop tower

Abstract

This paper solves two major problems which have blocked a free-fall Equivalence-Principle (EP) in a satellite for 25 years: a semimajor-axis error between the two proof masses cannot be distinguished from an EP violation and the response to an EP violation only grows as t not t^2. Using the cancellation method described in this paper, the nonobservability problem can be suppressed and a t^2 response can be generated which lasts between 10^4 and 10^6 seconds depending on the cancellation accuracy. t^2 response times between 10^5 and 10^6 seconds are equivalent to a very tall (0.1 to 10 AU) drop tower with a constant gravitational field of 3/7 ge.