Abstract
Recent theoretical ideas and observational claims suggest that the fine structure constant may be variable. We examine a spectrum of models in which is a function of a scalar field. Specifically, we consider three scenarios: oscillating , monotonic time variation of , and time-independent that is spatially varying. We examine the constraints imposed upon these theories by cosmological observations, particle detector experiments, and “fifth force” experiments. These constraints are very strong on models involving oscillation but cannot compete with bounds from the Oklo subnuclear reactor on models with monotonic timelike variation of . One particular model with spatial variation is consistent with all current experimental and observational measurements, including those from two seemingly conflicting measurements of the fine structure constant using the many multiplet method on absorption lines.
- Received 26 August 2003
DOI:https://doi.org/10.1103/PhysRevD.71.043509
©2005 American Physical Society