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Nissim Kanekar - National Radio Astronomy Observatory, Socorro

Wednesday, May 27 – 7:00-7:45PM


“Probing fundamental constant evolution with molecular spectroscopy”


Astrophysical studies of redshifted spectral lines from different molecular species provide a powerful probe of putative changes in low-energy fundamental constants across a large lookback time. After reviewing the current state of the field, I will describe our recent results from two radio studies, using comparisons between the redshifts of (1) “conjugate'' satellite OH 18cm lines, and (2) inversion and rotational lines, to test for changes in the fine structure constant, the proton-electron mass ratio and the proton gyro-magnetic ratio, over a large fraction of the age of the Universe.


Related Reference(s):

J. N. Chengalur and & N. Kanekar, “ Constraining the Variation of Fundamental Constants using 18 cm OH Lines,” Phys. Rev. Lett., 91, 241302, (2003).

V. V. Flambaum and M. G. Kozlov, “Limit on the Cosmological Variation of m p/m e from the Inversion Spectrum of Ammonia,” Phys. Rev. Lett., 98, 240801, (2007).

N. Kanekar, J. N. Chengalur, and T. Ghosh, “Conjugate 18 cm OH Satellite Lines at a Cosmological Distance,” Phys. Rev. Lett., 93, 051302 (2004).

N. Kanekar, “Do the Fundamental Constants Change with Time?” Mod. Phys. Lett., 23, 2711-2725 (2008).

M. T. Murphy, V. V. Flambaum, S. Muller, and C. Henkel, “Strong Limit on a Variable Proton-to-Electron Mass Ratio from Molecules in the Distant Universe,” Science, 320, 1611-1613 (2008).

J-P. Uzan, “The fundamental constants and their variation: observational and theoretical status,” Rev. Mod. Phys., 75, 403-455 (2003).