Time evolution of the fine structure constant

M. T. Murphy; J. K. Webb; V. V. Flambaum; S. J. Curran

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arXiv · astro-ph/0209488

Time evolution of the fine structure constant

M. T. Murphy·J. K. Webb·V. V. Flambaum·S. J. Curran

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Abstract

We present a short review of the current quasar (QSO) absorption line constraints on possible variation of the fine structure constant, alpha = e^2/(hbar*c). Particular attention is paid to recent optical Keck/HIRES spectra of 49 absorption systems which indicate a smaller alpha in the past (Murphy et al. 2001, Webb et al. 2001). Here we present new preliminary results from 128 absorption systems: da/a = (-0.57 +/- 0.10) x 10^{-5} over the redshift range 0.2 < z < 3.7, in agreement with the previous results. Known potential systematic errors cannot explain these results. We compare them with strong `local' constraints and discuss other (radio and millimetre-wave) QSO absorption line constraints on variations in alpha^2 * g_p and alpha^2 * g_p * m_e/m_p (g_p is the proton g-factor and m_e/m_p is the electron/proton mass ratio). Finally, we discuss future efforts to rule out or confirm the current 5.7 sigma optical detection.

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M. T. Murphy, J. K. Webb, V. V. Flambaum, S. J. Curran. 2002-09-24. Time evolution of the fine structure constant. https://arxiv.org/abs/astro-ph/0209488

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