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arXiv · 1704.08728

Fisher matrix forecasts for astrophysical tests of the stability of the fine-structure constant

C. S. Alves·T. A. Silva·C. J. A. P. Martins·A. C. O. Leite
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Abstract

We use Fisher Matrix analysis techniques to forecast the cosmological impact of astrophysical tests of the stability of the fine-structure constant to be carried out by the forthcoming ESPRESSO spectrograph at the VLT (due for commissioning in late 2017), as well by the planned high-resolution spectrograph (currently in Phase A) for the European Extremely Large Telescope. Assuming a fiducial model without $α$ variations, we show that ESPRESSO can improve current bounds on the Eötvös parameter---which quantifies Weak Equivalence Principle violations---by up to two orders of magnitude, leading to stronger bounds than those expected from the ongoing tests with the MICROSCOPE satellite, while constraints from the E-ELT should be competitive with those of the proposed STEP satellite. Should an $α$ variation be detected, these measurements will further constrain cosmological parameters, being particularly sensitive to the dynamics of dark energy.

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C. S. Alves, T. A. Silva, C. J. A. P. Martins, A. C. O. Leite. 2017-04-27. Fisher matrix forecasts for astrophysical tests of the stability of the fine-structure constant. https://doi.org/10.1016/j.physletb.2017.03.053

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