Zobrazeno 1 - 10
of 180
pro vyhledávání: '"Ospino, J."'
Publikováno v:
SYMMETRY, 16, 1422, (2024)
Exact solutions are presented which describe, either the evolution of fluid distributions corresponding to a ghost star (vanishing total mass), or describing the evolution of fluid distributions which attain the ghost star status at some point of the
Externí odkaz:
http://arxiv.org/abs/2411.04544
Publikováno v:
Symmetry 16, 562, (2024)
We explore an idea put forward many years ago by Zeldovich and Novikov concerning the existence of compact objects endowed with arbitrarily small mass. The energy-density of such objects, which we call ``Ghost stars'', is negative in some regions of
Externí odkaz:
http://arxiv.org/abs/2405.09480
Publikováno v:
Symmetry, 16, 341, (2024)
A semi--numerical approach proposed many years ago for describing gravitational collapse in the post--quasi--static approximation, is modified in order to avoid the numerical integration of the basic differential equations the approach is based upon.
Externí odkaz:
http://arxiv.org/abs/2403.07550
Publikováno v:
Phys. Rev. D 109, 024005 (2024)
It is shown that the evolution of an axially and reflection symmetric fluid distribution, satisfying the Tolman condition for thermal equilibrium, is not accompanied by the emission of gravitational radiation. This result, which was conjectured by Bo
Externí odkaz:
http://arxiv.org/abs/2401.05959
Publikováno v:
Entropy 25, 1338 (2023)
We carry out a systematic study on the motion of test particles in the region inner to the naked singularity of a quasi--hyperbolically symmetric $\gamma$-metric. The geodesic equations are written and analyzed in detail. The obtained results are con
Externí odkaz:
http://arxiv.org/abs/2309.08409
Publikováno v:
Symmetry, 15, 754, (2023)
We search exact analytical solutions of spherically symmetric dissipative fluid distributions satisfying the vanishing expansion condition (vanishing expansion scalar $\Theta$). To do so we shall impose additional restrictions allowing the integratio
Externí odkaz:
http://arxiv.org/abs/2302.04520
Publikováno v:
Universe 8, 296, (2022)
We carry on a general study on non--static spherically symmetric fluids admitting a conformal Killing vector (CKV). Several families of exact analytical solutions are found for different choices of the CKV, in both, the dissipative and the adiabatic
Externí odkaz:
http://arxiv.org/abs/2206.02143
Recent observations of the orbits of star clusters around Sgr $A^\star$, imaging of black holes and gravitational waveforms of merging compact objects require a detailed understanding of the general relativistic geodesic motion. We came up with a met
Externí odkaz:
http://arxiv.org/abs/2202.12415
Publikováno v:
Entropy 23, 1219, (2021)
We study fluid distributions endowed with hyperbolical symmetry, which share many common features with Lemaitre-Tolman-Bondi (LTB) solutions (e.g. they are geodesic, shearing, non--conformally flat and the energy density is inhomogeneous). As such th
Externí odkaz:
http://arxiv.org/abs/2110.01888
Publikováno v:
Symmetry 13, 1568, (2021)
We study the general properties of dissipative fluid distributions endowed with hyperbolical symmetry. Their physical properties are analyzed in detail. It is shown that the energy density is necessarily negative and the fluid distribution cannot fil
Externí odkaz:
http://arxiv.org/abs/2109.07758