12 papers
Semiclassical Black Hole-White Hole transitions: an analytical treatment
Julio Arrechea, Stefano Liberati, Massimiliano Spadafora
Recent numerical studies of semiclassical gravity suggest that, in spherically symmetric black holes with both outer and inner horizons, the semiclassical instability of the inner…
A parity selection rule for regular black holes
Farid Thaalba, Julio Arrechea, Stefano Liberati
Regular black hole metrics are usually studied kinematically, but a finite-curvature static core does not guarantee that the underlying theory can consistently evolve generic matte…
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…
Vacuum polarization and renormalized stress-energy tensor of spherical thin shells
Julio Arrechea, Cormac Breen, Adrian Ottewill +2
We provide a thorough study of the properties of the Boulware vacuum in the spacetime of a spherical, static thin shell with a Minkowski interior. To this end, we calculate the ren…
Cone hierarchy and the screening of matter by gravity
Julio Arrechea, Carlos Barceló, Gil Jannes
In a previous paper by some of the authors (Gen. Rel. Grav. 56, 116, 2024), we introduced a novel paradigm with which to understand gravitational phenomena. We called it the Harmon…
From de Sitter to anti-de Sitter singularity regularization: Theory and phenomenology
Julio Arrechea, Stefano Liberati, Hooman Neshat +1
Recent investigations of vacuum polarization in extremely compact stars suggest that, in such regimes, the effective matter content of spacetime may acquire a vacuum-energy equatio…