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We study the quasi-normal modes (QNMs) of a family of generalized black bounces interpolating between regular black holes and traversable wormhole solutions according to a single extra parameter $a$. Firstly, working with a generic…

General Relativity and Quantum Cosmology · Physics 2025-06-13 Albert Duran-Cabacés , Diego Rubiera-Garcia , Diego Sáez-Chillón Gómez

Using a noncommutative inspired Einstein-Euler-Heisenberg black hole, we analyse the associated graviton and light rings that together with the event horizon, provide the necessary components to build its shadow. An analysis of the angular…

General Relativity and Quantum Cosmology · Physics 2021-10-27 Marco Maceda , Alfredo Macías , Daniel Martínez-Carbajal

We model the dynamical evolution of star forming regions with a wide range of initial properties. We follow the evolution of the regions' substructure using the Q-parameter, we search for dynamical mass segregation using the Lambda_MSR…

Astrophysics of Galaxies · Physics 2015-06-17 Richard J. Parker , Nicholas J. Wright , Simon P. Goodwin , Michael R. Meyer

We introduce a simple analytic model of galaxy formation that links the growth of dark matter haloes in a cosmological background to the build-up of stellar mass within them. The model aims to identify the physical processes that drive the…

Astrophysics of Galaxies · Physics 2020-01-08 Jaime Salcido , Richard G. Bower , Tom Theuns

Recent work has shown that scalar fields around black holes can form long-lived, quasistationary configurations surviving for cosmological timescales. With this requirement, scalar fields cannot be discarded as viable candidates for dark…

General Relativity and Quantum Cosmology · Physics 2015-11-05 Nicolas Sanchis-Gual , Juan Carlos Degollado , Pedro J. Montero , José A. Font , Vassilios Mewes

We present Jordan-Brans-Dicke and general scalar-tensor gravitational theory in extra dimensions in an asymptotically flat or anti de Sitter spacetime. We consider a special gravitating, boson field configuration, a $q$-star, in 3, 4, 5 and…

High Energy Physics - Theory · Physics 2015-06-26 Athanasios Prikas

We show that oscillating (real-scalar) boson stars can act as strictly periodic gravitational lenses and generically host an \emph{oscillating radial caustic}. Sources near this caustic cross it every half period, producing achromatic…

General Relativity and Quantum Cosmology · Physics 2025-11-26 Xing-Yu Yang , Tan Chen , Rong-Gen Cai

The classical equations of motion for an axion with potential $V(\phi)=m_a^2f_a^2 [1-\cos (\phi/f_a)]$ possess quasi-stable, localized, oscillating solutions, which we refer to as "axion stars". We study, for the first time, collapse of…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-05 Thomas Helfer , David J. E. Marsh , Katy Clough , Malcolm Fairbairn , Eugene A. Lim , Ricardo Becerril

We present a detailed study of a X -ray selected sample of 5 submillimeter bright QSOs at $z\sim2$, where the highest rates of star formation (SF) and further growth of black holes (BH) occur. Therefore, this sample is a great laboratory to…

Astrophysics of Galaxies · Physics 2014-12-04 A. Khan-Ali , F. J. Carrera , M. J. Page , J. A. Stevens , S. Mateos , M. Symeonidis , J. M. Cao Orjales

Kerr black holes coupled to quantized bosonic fields display a special version of the Hawking effect, governed by the superradiance condition. This leads to rapid growth of boson cloud through spontaneous creation, leading to slowing down…

General Relativity and Quantum Cosmology · Physics 2020-02-27 Rittick Roy , Urjit A. Yajnik

We study a scalar field theory with a non-standard kinetic term minimally coupled to gravity. We establish the existence of compact boson stars, that is, static solutions with compact support of the full system with self-gravitation taken…

High Energy Physics - Theory · Physics 2011-04-20 C. Adam , N. Grandi , P. Klimas , J. Sanchez-Guillen , A. Wereszczynski

In this work, we find exact gravastar solutions in the context of noncommutative geometry, and explore their physical properties and characteristics. The energy density of these geometries is a smeared and particle-like gravitational…

General Relativity and Quantum Cosmology · Physics 2013-12-16 Francisco S. N. Lobo , Remo Garattini

We complete the analysis of part I in this series (Ref. \cite{Stotyn:2013yka}) by numerically constructing boson stars in 2+1 dimensional Einstein gravity with negative cosmological constant, minimally coupled to a complex scalar field.…

High Energy Physics - Theory · Physics 2014-02-19 Sean Stotyn , Melanie Chanona , Robert B. Mann

Recent fully non-linear simulations of ultracompact spherically symmetric boson stars have presented evidence for their long-term stability. All observed dynamics could be mainly attributed to the fundamental radial mode. In this work, we…

General Relativity and Quantum Cosmology · Physics 2026-04-06 Seppe J. Staelens

The time evolution of a set of 22 Mo unstable charged stars that collapse is computed integrating the Einstein-Maxwell equations. The model simulate the collapse of an spherical star that had exhausted its nuclear fuel and have or acquires…

Astrophysics · Physics 2007-05-23 Cristian R. Ghezzi , Patricio S. Letelier

We analyze the dynamics of a gravitational bounded cloud of generic bosons or a boson star in the non-relativistic regime, assuming from the very beginning that the boson star is in a Bose-Einstein condensed state. Also, we have taken into…

General Relativity and Quantum Cosmology · Physics 2024-11-05 Jorge Mastache , Elías Castellanos , Guillermo Chacón-Acosta

We present the results of a numerical simulation in which star formation proceeds from an initially unbound molecular cloud core. The turbulent motions, which dominate the dynamics, dissipate in shocks leaving a quiescent region which…

Astrophysics · Physics 2009-11-10 Paul C. Clark , Ian A. Bonnell

This work is devoted to the study of photon trajectories around rotating boson stars. The basic properties of boson star models are given with a particular emphasis on the high compactness those objects can have. Using an effective…

General Relativity and Quantum Cosmology · Physics 2017-04-12 Philippe Grandclément

I dynamically evolve spherically symmetric spacetimes containing gravitational 't Hooft-Polyakov monopoles and determine the stable end states of the evolutions. I do so to study stability and critical behavior of the well-known static…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Ben Kain

A new solution for the endpoint of gravitational collapse is proposed. By extending the concept of Bose-Einstein condensation to gravitational systems, a cold, compact object with an interior de Sitter condensate phase and an exterior…

General Relativity and Quantum Cosmology · Physics 2023-02-16 Pawel O. Mazur , Emil Mottola