collaborators

6 papers

gr-qc2026

Observational Tests of Regular Black Holes with Scalar Hair and their Stability

P. A. González, Marco Olivares, Eleftherios Papantonopoulos +1

We study the geodesic structure and observable properties of asymptotically flat regular black holes sourced by a phantom scalar field characterized by a scalar charge . This pa…

astro-ph.CO2026

Bulk viscous cosmological models with a cosmological constant: Observational constraints

R. Noemí Villalobos, Yerko Vásquez, Norman Cruz +1

We investigate whether viscous cold dark matter (vCDM) in a -dominated FLRW universe can alleviate the Hubble tension while satisfying thermodynamic constraints, examining both…

gr-qc2025

Near-horizon Geodesic Instabilities and Anomalous Decay of Quasinormal Modes in Weyl Black Holes

Gerasimos Kouniatalis, P. A. González, Eleftherios Papantonopoulos +1

We study the stability of the Weyl geometry considering an exact black hole solution. By calculating the geodesics of massless and massive scalar fields orbiting outside the Weyl b…

gr-qc2025

Massive Particle Motion Around Horndeski Black Holes

D. A. Carvajal, P. A. González, Marco Olivares +2

The time-like structure of the four-dimensional asymptotically flat Horndeski black holes is studied in detail. Focusing on the motion of massive neutral test particles, we constru…

gr-qc2025

Study of Null Geodesics and their Stability in Horndeski Black Holes

D. A. Carvajal, P. A. González, Marco Olivares +2

We study the motion of particles in the background of a scalar-tensor theory of gravity in which the scalar field is kinetically coupled to the Einstein tensor and we present the n…

gr-qc2025

Massive scalar field perturbations of 4D de Sitter Einstein-Gauss-Bonnet black holes

Ramón Bécar, P. A. González, Eleftherios Papantonopoulos +1

We investigate the propagation of massive scalar fields in the background of four-dimensional Einstein-Gauss-Bonnet black holes with de Sitter (dS) asymptotics. Our study focuses o…