1.4k citations · 4.8k across the 88 of their papers we have counts for
91 papers
States of low energy in the Schwinger effect
Álvaro Álvarez-Domínguez, Luis J. Garay, Mercedes Martín-Benito +1
States of low energy in cosmology minimise the energy density when smeared in a chosen time interval. We extend such construction to generic homogeneous (possibly anisotropic) part…
Operational realization of quantum vacuum ambiguities
Álvaro Álvarez-Domínguez, José A. R. Cembranos, Luis J. Garay +3
We provide a reinterpretation of the quantum vacuum ambiguities that one encounters when studying particle creation phenomena due to an external and time-dependent agent. We propos…
Late vacuum choice and slow roll approximation in gravitational particle production during reheating
Jose A. R. Cembranos, Luis J. Garay, Álvaro Parra-López +1
In the transition between inflation and reheating, the curvature scalar typically undergoes oscillations which have significant impact on the density of gravitationally produced pa…
Embedding Unimodular Gravity in String Theory
Luis J. Garay, Gerardo García-Moreno
Unimodular Gravity is a theory displaying Weyl rescalings of the metric and transverse (volume-preserving) diffeomorphisms as gauge symmetries, as opposed to the full set of diffeo…
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…
Warp Drive Aerodynamics
Carlos Barceló, Valentin Boyanov, Luis J. Garay +2
In this work we analyse the potential for a warp drive spacetime to develop instabilities due to the presence of quantum matter. Particularly, we look for points of infinite bluesh…
Causal structure of accelerating black holes
Jose A. R. Cembranos, Luis J. Garay, Sergio A. Ortega
Accelerating black holes are described by the so-called C-metric. In this work, we analyse the causal structure of such black holes by using null geodesics. We construct explicitly…
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…
Noether charge formalism for Weyl invariant theories of gravity
Ana Alonso-Serrano, Luis J. Garay, Marek Liška
Gravitational theories invariant under transverse diffeomorphisms and Weyl transformations have the same classical solutions as the corresponding fully diffeomorphism invariant the…
Noether charge formalism for Weyl transverse gravity
Ana Alonso-Serrano, Luis J. Garay, Marek Liška
Weyl transverse gravity is a gravitational theory that is invariant under transverse diffeomorphisms and Weyl transformations. It is characterised by having the same classical solu…
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…
Generalized quantum Vlasov equation for particle creation and unitary dynamics
Álvaro Álvarez-Domínguez, Luis J. Garay, Mercedes Martín-Benito
The loss of time-translational invariance caused by a time-dependent external agent leads to particle creation effects in quantum field theory. This phenomenon results in ambiguiti…
Breaking Buchdahl: ultracompact stars in semiclassical gravity
Julio Arrechea, Carlos Barceló, Raúl Carballo-Rubio +1
The semiclassical approximation takes into account the gravitational contribution of zero-point energies. We model this contribution via the renormalized stress-energy tensor (RSET…
Semiclassical relativistic stars
Julio Arrechea, Carlos Barceló, Raúl Carballo-Rubio +1
We present strong evidence that semiclassical gravity can give place to self-consistent ultracompact stars beyond the Buchdahl limit. We integrate the semiclassical equations of (s…
Toward a mechanism for the emergence of gravity
Carlos Barceló, Raúl Carballo-Rubio, Luis J. Garay +1
One of the main problems that emergent-gravity approaches face is explaining how a system that does not contain gauge symmetries ab initio might develop them effectively in some re…
The time traveler's guide to the quantization of zero modes
Ana Alonso-Serrano, Erickson Tjoa, Luis J. Garay +1
We study the relationship between the quantization of a massless scalar field on the two-dimensional Einstein cylinder and in a spacetime with a time machine. We find that the latt…
A detector-based measurement theory for quantum field theory
José Polo-Gómez, Luis J. Garay, Eduardo Martín-Martínez
We propose a measurement theory for quantum fields based on measurements made with localized non-relativistic systems that couple covariantly to quantum fields (like the Unruh-DeWi…
Quantum unitary dynamics of a charged fermionic field and Schwinger effect
Álvaro Álvarez-Domínguez, Luis J. Garay, David García-Heredia +1
In quantum field theory, particle creation occurs, in general, when an intense external field, such as an electromagnetic field, breaks time translational invariance. This leads to…
Semiclassical constant-density spheres in a regularized Polyakov approximation
Julio Arrechea, Carlos Barceló, Raúl Carballo-Rubio +1
We provide an exhaustive analysis of the complete set of solutions of the equations of stellar equilibrium under semiclassical effects. As classical matter we use a perfect fluid o…
Analogue gravity simulation of superpositions of spacetimes
Carlos Barceló, Luis J. Garay, Gerardo García-Moreno
Taking the principles of quantum mechanics as they stand and applying them to gravity, leads to the conclusion that one might be able to generate superpositions of spacetimes, at l…
Reissner-Nordström geometry counterpart in semiclassical gravity
Julio Arrechea, Carlos Barceló, Raúl Carballo-Rubio +1
We compute the Renormalized Stress-Energy Tensor (RSET) of a massless minimally coupled scalar field in the Regularized Polyakov approximation, as well as its backreaction, on the…
Emergent gauge symmetries: Yang-Mills theory
Carlos Barceló, Raúl Carballo-Rubio, Luis J. Garay +1
Gauge symmetries remove unphysical states and guarantee that field theories are free from the pathologies associated with these states. In this work we find a set of general condit…
Inversion of statistics and thermalization in the Unruh effect
Julio Arrechea, Carlos Barceló, Luis J. Garay +1
We derive a master equation for the reduced density matrix of a uniformly accelerating quantum detector in arbitrary dimensions, generically coupled to a field initially in its vac…
Black hole inner horizon evaporation in semiclassical gravity
Carlos Barceló, Valentin Boyanov, Raúl Carballo-Rubio +1
In this work we analyse the backreaction of a quantum field on a spherically symmetric black hole geometry with an inner horizon, i.e. an internal boundary of the trapped region. W…