June-2017 Colloquium

Date : 21-06-2017
Time : 15:45:00
Speaker : Dr. Nissim Kanekar
Associate Professor
Area : DEAN'S OFFICE
Venue : K. R. Ramanathan Auditorium,PRL

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, and will describe new high-sensitivity results from these methods. Finally, 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.