Varying Fine Structure Constant and the Runaway Dilaton

The Runaway Dilaton couples to the fine-structure constant. We can thus use measurements of possible fine-structure constant to constrain the runaway dilaton field. By using Monte-Carlo Markov Chains (MCMC) on the free parameters in the runaway dilaton equation of motion using Principal Component Analysis (PCA) of fine-structure constant variation, we can constrain the allowed values of these parameters. Work so far indicates that the parameter space is largely (though not entirely) unconstrained with regard to current observational limits on allowed fine-structure constant variation.