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Critical Phenomena in the Einstein-Massless-Dirac System

Jason F. Ventrella·Matthew W. Choptuik
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Abstract

We investigate the general relativistic collapse of spherically symmetric, massless spin-1/2 fields at the threshold of black hole formation. A spherically symmetric system is constructed from two spin-1/2 fields by forming a spin singlet with no net spin-angular momentum. We study the system numerically and find strong evidence for a Type II critical solution at the threshold between dispersal and black hole formation, with an associated mass scaling exponent $γ~ 0.26$. Although the critical solution is characterized by a continuously self-similar (CSS) geometry, the matter fields exhibit discrete self-similarity with an echoing exponent $Δ~ 1.34$. We then adopt a CSS ansatz and reduce the equations of motion to a set of ODEs. We find a solution of the ODEs that is analytic throughout the solution domain, and show that it corresponds to the critical solution found via dynamical evolutions.

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Jason F. Ventrella, Matthew W. Choptuik. 2003-04-01. Critical Phenomena in the Einstein-Massless-Dirac System. https://doi.org/10.1103/physrevd.68.044020

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