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arXiv · 2105.12672

Nonlinear effects in the excited states of many-fermion Einstein-Dirac solitons

Peter E. D. Leith·Chris A. Hooley·Keith Horne·David G. Dritschel
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Abstract

We present an analysis of excited-state solutions for a gravitationally localized system consisting of a filled shell of high-angular-momentum fermions, using the Einstein-Dirac formalism introduced by Finster, Smoller, and Yau [Phys. Rev. D 59, 104020 (1999)]. We show that, even when the particle number is relatively low ($N_f\ge 6$), the increased nonlinearity in the system causes a significant deviation in behavior from the two-fermion case. Excited-state solutions can no longer be uniquely identified by the value of their central redshift, with this multiplicity producing distortions in the characteristic spiraling forms of the mass-radius relations. We discuss the connection between this effect and the internal structure of solutions in the relativistic regime.

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Peter E. D. Leith, Chris A. Hooley, Keith Horne, David G. Dritschel. 2021-05-26. Nonlinear effects in the excited states of many-fermion Einstein-Dirac solitons. https://doi.org/10.1103/physrevd.104.046024

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