192 citations · 2.2k across the 68 of their papers we have counts for
69 papers
Charging up regular black holes
Raúl Carballo-Rubio, Chiara Coviello, Vania Vellucci
We present a general construction of charged regular black holes as solutions of a generalization of the Einstein--Maxwell field equations in spherical symmetry in which the Einste…
Semiclassical regularity of compact trapped regions: From dynamical horizons to inner extremality
Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati +1
In eternal black-hole spacetimes, inner horizons are Cauchy horizons and are generically unstable. For non-extremal inner horizons, this includes both the classical mass-inflation…
Effective geometrostatics of spherical stars beyond general relativity
Julio Arrechea, Raúl Carballo-Rubio, Matt Visser
We provide a set of general tools to study the problem of stellar equilibrium in any gravitational theory in which spherically symmetric spacetimes satisfy master field equations t…
Regular black holes from pure gravity in four dimensions
Johanna Borissova, Raúl Carballo-Rubio
We derive static spherically symmetric regular black holes as vacuum solutions to purely gravitational theories in four dimensions. To that end, we construct four-dimensional non-p…
Effective geometrodynamics for renormalization-group improved black-hole spacetimes in spherical symmetry
Johanna Borissova, Raúl Carballo-Rubio
We consider the spherically reduced Einstein-Hilbert action, Einstein field equations and Schwarzschild spacetime modified by a renormalization-group (RG) scale-dependent gravitati…
Macroscopic backreaction of the trace anomaly on classical vacuum backgrounds
Raúl Carballo-Rubio, Francesco Di Filippo, Shinji Mukohyama +1
We study the backreaction of quantum fields in the Boulware vacuum state on the Schwarzschild geometry, using the Riegert--Mottola--Vaulin renormalized stress-energy tensor derived…
Imprints of quantum vacuum fluctuations on the gravitational field of a spherical mass
Raúl Carballo-Rubio, Francesco Di Filippo, Shinji Mukohyama +1
The Schwarzschild geometry, describing the gravitational field of a spherical mass in classical vacuum, is one of the most famous vacuum solutions of the Einstein field equations.…
Master field equations for spherically symmetric gravitational fields beyond general relativity
Raúl Carballo-Rubio
According to general relativity, black holes are incomplete, which prevents developing a complete physical description of their dynamical formation and evolution once quantum effec…
Regular Vaidya solutions of effective gravitational theories
Valentin Boyanov, Raúl Carballo-Rubio
We initiate the study of the dynamics of spherically symmetric spacetimes beyond general relativity through exact solutions of the field equations of second-order effective gravita…
No-hair and almost-no-hair results for static axisymmetric black holes and ultracompact objects in astrophysical environments
Carlos Barceló, Raúl Carballo-Rubio, Luis J. Garay +1
No-hair theorems are uniqueness results constraining the form of the metric of black holes in general relativity. These theorems are typically formulated under idealized assumption…
Geodesically complete universes
Raúl Carballo-Rubio, Stefano Liberati, Vania Vellucci
Singularity theorems demonstrate the inevitable breakdown of the concept of continuous, classical spacetime under highly general conditions. Quantum gravity is expected to interven…
Mass inflation without Cauchy horizons
Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati +1
Mass inflation is a well established instability, conventionally associated to Cauchy horizons (which are also inner trapping horizons) of stationary geometries, leading to a diver…
Ultracompact horizonless objects in order-reduced semiclassical gravity
Julio Arrechea, Carlos Barceló, Raúl Carballo-Rubio +1
The backreaction of quantum fields in their vacuum state results in equilibrium structures that surpass the Buchdahl compactness limit. Such backreaction is encapsulated in the vac…
Constraints on thermalizing surfaces from infrared observations of supermassive black holes
Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati +1
Infrared observations of Sgr A and M87 are incompatible with the assumption that these sources have physical surfaces in thermal equilibrium with their accreting environmen…
Singularity-free gravitational collapse: From regular black holes to horizonless objects
Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati +1
Penrose's singularity theorem implies that if a trapped region forms in a gravitational collapse, then a singularity must form as well within such region. However, it is widely exp…
Asymptotically flat vacuum solutions in order-reduced semiclassical gravity
Julio Arrechea, Carlos Barceló, Raúl Carballo-Rubio +1
We investigate the effects of quantum backreaction on the Schwarzschild geometry in the semiclassical approximation. The renormalized stress-energy tensor (RSET) of a scalar field…
Comment on "Regular evaporating black holes with stable cores"
Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati +2
Regular black holes are generically unstable because of the classical phenomenon that goes by the name of "mass inflation" which destabilizes the inner horizon. In a recent article…
A connection between regular black holes and horizonless ultracompact stars
Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati +1
We illustrate that regular black holes and horizonless stars, typically considered as quite distinct families of black hole mimickers, are intimately intertwined. We show that any…
Towards VLBI Observations of Black Hole Structure
Raúl Carballo-Rubio, Vitor Cardoso, Ziri Younsi
Black holes hold a tremendous discovery potential. In this paper the extent to which the Event Horizon Telescope and its next generation upgrade can resolve their structure is quan…
Unimodular Gravity vs General Relativity: A status report
Raúl Carballo-Rubio, Luis J. Garay, Gerardo García-Moreno
Unimodular Gravity is an alternative to General Relativity (GR) which, however, is so closely related to the latter that one can wonder to what extent they are different. The diffe…
Regular black holes without mass inflation instability
Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati +2
Generic models of regular black holes have separate outer and inner horizons, both with nonzero surface gravity. It has been shown that a nonzero inner horizon surface gravity resu…
Constraints on horizonless objects after the EHT observation of Sagittarius A*
Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati +1
The images of Sagittarius A recently released by the Event Horizon Telescope collaboration have been accompanied [Ap.J.Lett.\,{\bf 930\,\#2}\,(2022)\,L17] by an analysis of the…
On the inner horizon instability of non-singular black holes
Francesco Di Filippo, Raúl Carballo-Rubio, Stefano Liberati +2
Regular black holes represent a conservative model in which the classical singularity is replaced by a non-singular core without necessarily modifying the spacetime outside the tra…
Classical mass inflation vs semiclassical inner horizon inflation
Carlos Barceló, Valentin Boyanov, Raúl Carballo-Rubio +1
We analyse the geometry of a spherically symmetric black hole with an inner and outer apparent horizon which is perturbed by spherical null shells of matter. On a classical level w…