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arXiv · 0706.2873

Astrophysical Violations of the Kerr Bound as a Possible Signature of String Theory

Eric G. Gimon·Petr Horava
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Abstract

In 4D general relativity, the angular momentum of a black hole is limited by the Kerr bound. We suggest that in string theory, this bound can be breached and compact black-hole-like objects can spin faster. Near such "superspinars," the efficiency of energy transfer from the accreting matter to radiation can reach 100%, compared to the maximum efficiency of 42% of the extremal Kerr (or 6% of the Schwarzschild) black hole. Finding such superspinning objects as active galactic nuclei, GBHCs, or sources of gamma ray bursts, could be viewed as experimental support for string theory.

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Eric G. Gimon, Petr Horava. 2007-06-19. Astrophysical Violations of the Kerr Bound as a Possible Signature of String Theory. https://doi.org/10.1016/j.physletb.2009.01.026

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