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arXiv · 1012.1343

The vacuum revealed: the final state of vacuum instabilities in compact stars

Paolo Pani·Vitor Cardoso·Emanuele Berti·Jocelyn Read·Marcelo Salgado
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Abstract

Quantum fields in compact stars can be amplified due to a semiclassical instability. This generic feature of scalar fields coupled to curvature may affect the birth and the equilibrium structure of relativistic stars. We point out that the semiclassical instability has a classical counterpart, which occurs exactly in the same region of the parameter space. For negative values of the coupling parameter the instability is equivalent to the well-known "spontaneous scalarization" effect: the plausible end-state of the instability is a static, asymptotically flat equilibrium configuration with nonzero expectation value for the quantum fields, which is compatible with experiments in the weak-field regime and energetically favored over stellar solutions in general relativity. For positive values of the coupling parameter the new configurations are energetically disfavored, and the end-point of the instability remains an open and interesting issue. The vacuum instability may provide a natural mechanism to produce spontaneous scalarization, leading to new experimental opportunities to probe the nature of vacuum energy via astrophysical observations of compact stars.

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Paolo Pani, Vitor Cardoso, Emanuele Berti, Jocelyn Read, Marcelo Salgado. 2010-12-06. The vacuum revealed: the final state of vacuum instabilities in compact stars. https://doi.org/10.1103/physrevd.83.081501

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