Dirac clouds around dilatonic black holes

Abstract

Dirac cloud is in absence in general relativity since the superradiance mechanism fails to work for Dirac fields. For the first time we find a novel mechanism to support Dirac clouds, which is independent on superradiance mechanism. We study quasi bound states of Dirac particles around a charged spherical black hole in dilatonic gravity. We find that the quasi bound states become real bound states when the central black hole becomes extremal. We make an intensive study of the energy spectrum of the stationary clouds for different fine structure constant $\mu M$, and reveal the existence condition of these clouds. Our result strongly implies that extreme dilatonic black holes behave as elementary particles.

9 pages, 7 figures, published in Research

References in corpus (7)

• Type-II Dirac fermions in the PtSe${}_2$ class of transition metal dichalcogenides
• Spherically Symmetric Scalar Hair for Charged Black Holes
• Scalar clouds and the superradiant instability regime of Kerr-Newman black hole
• Stationary Charged Scalar Clouds around Black Holes in String Theory
• Quasibound states of charged dilatonic black holes
• Scalar clouds around Kerr-Sen black holes
• Massive charged Dirac fields around Reissner-Nordström black holes: quasibound states and long-lived modes

Cited by in corpus (1)

• True gravitational atom: Spherical cloud of dilatonic black holes