Space-Time Variation of Physical Constants and the Equivalence Principle

TL;DR

This paper investigates how variations in fundamental physical constants over space and time can lead to violations of the equivalence principle, with implications for laboratory, space, and cosmological experiments.

Contribution

It provides a theoretical analysis linking spatial and temporal variations of constants to observable violations of free fall universality and constraints from experiments.

Findings

Spatial variations cause body accelerations detectable in lab and space tests.

Cosmological time variations are constrained by lunar laser ranging.

Variations imply a preferred frame affecting gravitational experiments.

Abstract

Location dependence of physical parameters such as the electromagnetic fine structure constant and Newton's G produce body accelerations which violate universality of free fall rates testable with laboratory and space experiments. Theoretically related cosmological time variation of these same parameters are also constrained by experiments such as lunar laser ranging, and these time variations produce accelerations of bodies relative to a preferred cosmological frame.