Dust collapse and horizon formation in Quadratic Gravity

Abstract

Quadratic Gravity supplements the Einstein-Hilbert action by terms quadratic in the spacetime curvature. This leads to a rich phase space of static, compact gravitating objects including the Schwarzschild black hole, wormholes, and naked singularities. For the first time, we study the collapse of a spherically symmetric star with uniform dust density in this setting. We assume that the interior geometry respects the symmetries of the matter configuration, i.e., homogeneity and isotropy, thus it is insensitive to the Weyl-squared term and the interior dynamics is fully determined by $R$ and $R^2$. As our main result, we find that the collapse leads to the formation of a horizon, implying that the endpoint of a uniform dust collapse with a homogeneous and isotropic interior is not a horizonless spacetime. We also show that the curvature-squared contribution is responsible for making the collapse into a singularity faster than the standard Oppenheimer-Snyder scenario. Furthermore, the junction conditions connecting spacetime inside and outside the matter distribution are found to be significantly more constraining than their counterparts in General Relativity and we discuss key properties of any exterior solution matching to the spacetime inside the collapsing star. Finally, we comment on the potentially non-generic behavior entailed by our assumptions.

V2: version published in JCAP

References in corpus (27)

• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way
• Black Holes in Higher-Derivative Gravity
• New Test of the Gravitational $1/r^2$ Law at Separations down to 52 $\mu$m
• Unitarity, stability and loops of unstable ghosts
• Physical observability of horizons
• Static Solutions for 4th order gravity
• The arrow of causality and quantum gravity
• Dust collapse in asymptotic safety: a path to regular black holes
• Black holes and other exact spherical solutions in Quadratic Gravity
• Instability of spherically-symmetric black holes in Quadratic Gravity
• Black Holes in Asymptotically Safe Gravity
• Not quite black holes at LIGO
• Instability and backreaction of massive spin-2 fields around black holes
• Probing Quadratic Gravity with the Event Horizon Telescope
• Nonlinear Evolution of Quadratic Gravity in 3+1 Dimensions
• Horizonless ultracompact objects and dark matter in quadratic gravity
• Foundations of ghost stability
• The gravitational field of a star in quadratic gravity
• Is gravitational collapse possible in $f(R)$ gravity?
• Novel black holes in higher derivative gravity
• The phase diagram of Einstein-Weyl gravity
• Effective action and black hole solutions in asymptotically safe quantum gravity
• 2-2-holes simplified
• Gravitational collapse in Quadratic Gravity
• Non-perturbative quantum gravity denounces singular Black Holes
• Well-posed initial value formulation of general effective field theories of gravity

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