Abstract:

 

Temporal evolution in low-energy fundamental constants such as the 

fine structure constant and the proton-electron mass ratio is a generic 

prediction of field theories that attempt to unify the Standard Model 

of particle physics and general relativity. The exciting possibility of 

low-energy tests of such unification theories has inspired a number of 

methods to probe fundamental constant evolution on a range of timescales, 

from years to billions of years. Astrophysical studies of redshifted spectral 

lines provide a powerful probe of such putative changes in the low-energy 

fundamental constants across a large fraction of the age of the Universe. 

After reviewing the current state of the field, I will focus on two techniques, 

based on radio spectral lines from the hydroxyl and methanol molecules detected in high-redshift galaxies, and will describe new high-sensitivity results from these methods. Finally, if time permits, I will discuss present 

limitations of such studies and the improvements that are likely to be 

possible with the advent of new experimental and observational facilities 

over the next decade.