Black holes may not constrain varying constants

S. Carlip; S. Vaidya

doi:10.1038/421498a

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arXiv · hep-th/0209249

Black holes may not constrain varying constants

S. Carlip·S. Vaidya

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Abstract

New and rather controversial observations hint that the fine structure constant αmay have been smaller in the early universe, suggesting that some of the fundamental ``constants'' of physics may be dynamical. In a recent paper, Davies, Davis, and Lineweaver have argued that black hole thermodynamics favors theories in which the speed of light c decreases with time, and disfavors those in which the fundamental electric charge e increases. We show that when one considers the full thermal environment of a black hole, no such conclusion can be drawn: thermodynamics is consistent with an increase in αwhether it comes from a decrease in c, an increase in e, or a combination of the two.

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S. Carlip, S. Vaidya. 2002-09-27. Black holes may not constrain varying constants. https://doi.org/10.1038/421498a

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