Victor Flambaum
University of New South Wales
Sydney
Tuesday, October 21st, 3.00pm
4th Floor, CSSM
DO THE FUNDAMENTAL CONSTANTS OF NATURE VARY WITH TIME AND DISTANCE?
Abstract:
Theories unifying gravity with other interactions suggest the spatial and temporal variation of the fundamental "constants" in the Universe. A change in the fine structure constant alpha=e^2/hc could be detected via shifts in the rest wavelengths of resonance transitions in quasar absorption systems. We have developed a new approach which improves the sensitivity of this method by an order of magnitude (Phys. Rev. Lett. 82, 888, 1999) and measured alpha in 140 absorption systems covering look-back times from 0.2 to 0.9 times the age of the Universe. Our initial results hinted that alpha may have been smaller in the past (Phys. Rev. Lett., 82, 884, 1999). Startlingly, new results based on 3 independent data sets support the same effect (Phys. Rev.Lett.87, 091301, 2001 and MNRAS,2003). These data have inspired a more general discussion of possible variation of other constants. We discuss variation of strong scale, quark masses and Plank mass (gravity). We derive the limits on their relative change from (i) primordial Big-Bang Nucleosynthesis; (ii) Oklo natural nuclear reactor, (iii) quasar absorption spectra, and (iv) atomic clocks (nuclear magnetic moments).