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Anomalous Fermion Production in Gravitational Collapse

G. W. Gibbons·Alan R. Steif
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Abstract

The Dirac equation is solved in the Einstein-Yang-Mills background found by Bartnik and McKinnon. We find a normalizable zero-energy fermion mode in the $s$-wave sector. As shown recently, their solution corresponds to a gravitational sphaleron which mediates transitions between topologically distinct vacua. Since the Bartnik-McKinnon solution is unstable, it will either collapse to form a black hole or radiate away its energy. In either case, as the Chern-Simons number of the configuration changes, there will be an accompanying anomalous change in fermion number.

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G. W. Gibbons, Alan R. Steif. 1993-05-24. Anomalous Fermion Production in Gravitational Collapse. https://doi.org/10.1016/0370-2693(93)91315-e

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