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arXiv · 1604.07092

Variations in the fine structure constant constraining gravity theories

V. B. Bezerra·M. S. Cunha·C. R. Muniz·M. O. Tahim·H. S. Vieira
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Abstract

In this paper, we investigate how the fine structure constant, $\alpha$, locally varies in the presence of a static and spherically symmetric gravitational source. The procedure consists in calculating the solution and the energy eigenvalues of a massive scalar field around that source, considering the weak-field regimen. From this result, we obtain expressions for an spatially variable fine structure constant by considering suitable modifications in the involved parameters admitting some scenarios of semi-classical and quantum gravities. Constraints on free parameters of the approached theories are calculated from astrophysical observations of the emission spectra of a white dwarf. Such constraints are finally compared with those ones obtained in the literature.

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V. B. Bezerra, M. S. Cunha, C. R. Muniz, M. O. Tahim, H. S. Vieira. 2016-04-24. Variations in the fine structure constant constraining gravity theories. https://doi.org/10.1209/0295-5075/115/40004

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