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Related papers: Ultracompact vector stars

200 papers

Boson stars have attracted much attention in recent decades as simple, self-consistent models of compact objects and also as self-gravitating structures formed in some dark-matter scenarios. Direct detection of these hypothetical objects…

General Relativity and Quantum Cosmology · Physics 2022-09-20 Miguel Bezares , Mateja Bošković , Steven Liebling , Carlos Palenzuela , Paolo Pani , Enrico Barausse

We show that a vector field non-minimally coupled to gravity reproduces exactly the dynamics of an Einstein cluster -- a large ensemble of non-interacting particles moving on circular geodesics under their collective gravitational field.…

General Relativity and Quantum Cosmology · Physics 2026-04-17 Pedro G. S. Fernandes , Vitor Cardoso

The origin of ultra-intense magnetic fields on magnetars is a mystery in modern astrophysics. We model the core collapse dynamics of massive progenitor stars with high surface magnetic fields in the theoretical framework of a self-similar…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Ren-Yu Hu , Yu-Qing Lou

We study the linear response of four dimensional magnetized black holes and regular topological stars arising from dimensional compactification of Einstein-Maxwell theory in five dimensions. We consider both radial and nonradial…

General Relativity and Quantum Cosmology · Physics 2024-10-03 Alexandru Dima , Marco Melis , Paolo Pani

The recent theoretical advance known as the Minimal Geometric Deformation (MGD) method has initiated a renewed interest in investigating higher curvature gravitational effects in relativistic astrophysics. In this work, we model a strange…

General Relativity and Quantum Cosmology · Physics 2022-02-16 S. K. Maurya , Ksh. Newton Singh , M. Govender , Sudan Hansraj

Optical singularities manifesting at the center of vector vortex beams are unstable, since their topological charge is higher than the lowest value permitted by Maxwell's equations. Inspired by conceptually similar phenomena occurring in…

We present novel neutral and uncharged solutions that describe the cluster of Einstein in the teleparallel equivalent of general relativity (TEGR). To this end, we use a tetrad field with non-diagonal spherical symmetry which gives the…

General Relativity and Quantum Cosmology · Physics 2023-11-22 G. G. L. Nashed , Amare Abebe , Kazuharu Bamba

Gravitational vacuum condensate stars, also known as gravastars, have been proposed as an alternative to black holes. Their interior contains a perfect fluid with an equation of state akin to that of a cosmological constant. For this…

General Relativity and Quantum Cosmology · Physics 2023-08-16 P. P. Avelino

The discovery of hypervelocity stars (HVS) leaving our galaxy with speeds of nearly $10^{3}$ km s$^{-1}$ has provided strong evidence towards the existence of a massive compact object at the galaxy's center. HVS ejected via the disruption…

Astrophysics of Galaxies · Physics 2015-06-18 James Guillochon , Abraham Loeb

A summary of the current knowledge on hypervelocity stars (HVSs). HVSs are fascinating because their properties are linked to Sgr A* and the stellar environment of the Galactic Center. Observing the distribution of HVSs can address: 1) the…

Astrophysics · Physics 2008-11-05 Warren R. Brown

Supermassive black holes in the centre of galaxies dominate the gravitational potential of their surrounding stellar clusters. In these dense environments, stars follow nearly Keplerian orbits, which get slowly distorted as a result of the…

There is increasing observational evidence for the existence of strange stars: ultra-compact objects whose interior consists entirely of deconfined quark matter. If confirmed, their existence places constraints on the rate of formation of…

Astrophysics · Physics 2007-05-23 Peter Gorham , John Learned , Nikolai Lehtinen

We investigate whether compact stars having Tolman-like interior geometry admit conformal symmetry. Taking anisotropic pressure along the two principal directions within the compact object, we obtain physically relevant quantities such as…

General Relativity and Quantum Cosmology · Physics 2016-07-25 Farook Rahaman , Sunil D. Maharaj , Iftikar Hossain Sardar , Koushik Chakraborty

It is thought that magnetic fields must be present in the interiors of stars to resolve certain discrepancies between theory and observation (e.g. angular momentum transport), but such fields are difficult to detect and characterise.…

Solar and Stellar Astrophysics · Physics 2021-04-21 Shyeh Tjing Loi

In the context of the standard model of particle physics, there is a definite upper limit to the density of stable compact stars. However, if there is a deeper layer of constituents, below that of quarks and leptons, stability may be…

Astrophysics · Physics 2014-10-13 F. Sandin

The auto-correlation between two members of a galaxy population is symmetric under the interchange of the two galaxies being correlated. The cross-correlation between two different types of galaxies, separated by a vector $\bf{r}$, is not…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-11 Liang Dai , Marc Kamionkowski , Ely D. Kovetz , Alvise Raccanelli , Maresuke Shiraishi

We study a specific model of anisotropic strange stars in the modified $f\left(R,\mathcal{T}\right)$-type gravity by deriving solutions to the modified Einstein field equations representing a spherically symmetric anisotropic stellar…

General Relativity and Quantum Cosmology · Physics 2019-05-01 Debabrata Deb , Sergei V. Ketov , S. K. Maurya , Maxim Khlopov , P. H. R. S. Moraes , Saibal Ray

A covariant scalar-tensor-vector gravity theory is developed which allows the gravitational constant $G$, a vector field coupling $\omega$ and the vector field mass $\mu$ to vary with space and time. The equations of motion for a test…

General Relativity and Quantum Cosmology · Physics 2021-11-22 J. W. Moffat

Twenty years have passed since the discovery of the accelerated expansion of the Universe, reviving the interest for alternative theories of gravity. Adding a scalar degree of freedom to the usual metric of general relativity is one of the…

General Relativity and Quantum Cosmology · Physics 2018-10-11 Antoine Lehébel

The manifesto of the current article is to investigate the compact anisotropic matter profiles in the context of one of the modified gravitational theories, known as $f(\mathcal{R}, \mathcal{T})$ gravity, where $\mathcal{R}$ is a Ricci…

General Relativity and Quantum Cosmology · Physics 2021-01-05 G. Mustafa , Xia Tie-Cheng , Mushtaq Ahmad , M. Farasat Shamir