English
Related papers

Related papers: Polytropic spheres containing regions of trapped n…

200 papers

We present forecasted cosmological constraints from combined measurements of galaxy cluster abundances from the Simons Observatory and galaxy clustering from a DESI-like experiment on two well-studied modified gravity models, the…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 Rayne Liu , Georgios Valogiannis , Nicholas Battaglia , Rachel Bean

We construct the marginal loosely trapped surface (marginal LTS) for the Kerr spacetime with a small Kerr parameter perturbatively, where the LTS condition is saturated. An LTS is a surface that specifies the strong gravity region, which is…

General Relativity and Quantum Cosmology · Physics 2024-07-17 Keisuke Izumi , Tetsuya Shiromizu , Daisuke Yoshida , Yoshimune Tomikawa , Hirotaka Yoshino

The macroscopic properties of compact stars in modified gravity theories can be significantly different from the general relativistic (GR) predictions. Within the gravitational context of scalar-tensor theories, with a scalar field $\phi$…

General Relativity and Quantum Cosmology · Physics 2023-12-05 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis , Sergio B. Duarte , José D. V. Arbañil

We study the sphere packing problem in Euclidean space where we impose additional constraints on the separations of the center points. We prove that any sphere packing in dimension $48$, with spheres of radii $r$, such that no two centers…

Number Theory · Mathematics 2025-03-05 Felipe Gonçalves , Guilherme Vedana

The surfaces of neutron stars are sources of strongly polarized soft X rays due to the presence of strong magnetic fields. Radiative transfer mediated by electron scattering and free-free absorption is central to defining local surface…

High Energy Astrophysical Phenomena · Physics 2022-04-06 Kun Hu , Matthew G. Baring , Joseph A. Barchas , George Younes

We study static spherically symmetric solutions to Einstein's equations with a repulsive singularity at the centre. We show that geodesics are extendible across the singularity, so the singularity does not lead to pathological causality…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Ntina Savvidou , Charis Anastopoulos

We obtain bounds on the stability of various self-gravitating astrophysical objects using a new measure of shape complexity known as configurational entropy. We apply the method to Newtonian polytropes, neutron stars with an…

General Relativity and Quantum Cosmology · Physics 2016-07-06 Marcelo Gleiser , Nan Jiang

An explicit necessary condition for the occurrence of resonance scattering of axial gravitational waves, along with the internal trapping of null geodesics, is proposed for static spherically symmetric perfect fluid solutions to Einstein's…

General Relativity and Quantum Cosmology · Physics 2010-02-23 Mustapha Ishak , Luke Chamandy , Nicholas Neary , Kayll Lake

Amorphous ice has long been invoked as a means for trapping extreme volatiles into solids, explaining the abundances of these species in comets and planetary atmospheres. Experiments have shown that such trapping is possible and have been…

Earth and Planetary Astrophysics · Physics 2018-11-28 Fred Ciesla , Sebastiaan Krijt , Reika Yokochi , Scott Sandford

It is generally agreed upon that the pressure inside a neutron star is isotropic. However, a strong magnetic field or superfluidity suggests that the pressure anisotropy may be a more realistic model. We derived the dimensionless TOV…

High Energy Astrophysical Phenomena · Physics 2024-09-05 Zhihao Yang , Dehua Wen

In this article, we consider `$N$'spherical caps of area $4\pi p$ were uniformly distributed over the surface of a unit sphere. We are giving the strong threshold function for the size of random caps to cover the surface of a unit sphere.…

Probability · Mathematics 2008-09-09 Bhupendra Gupta

This paper shows that gravitating bodies travelling through the Galaxy can trap lighter interstellar particles that pass nearby with small relative velocities onto temporarily-bound orbits. The capture mechanism is driven by the Galactic…

Astrophysics of Galaxies · Physics 2022-12-28 Jorge Peñarrubia

The interior of mature neutron stars is expected to contain superfluid neutrons and superconducting protons. The influence of temperature and currents on superfluid properties is studied within the self-consistent time-dependent nuclear…

Nuclear Theory · Physics 2026-05-21 Valentin Allard , Nicolas Chamel

In this paper, we focus on a marginally trapped submanifold $f:\Sigma^n\to M^{n+2}_1$ in a Lorentzian manifold $M^{n+2}_1$. We show that $f$ lies in a certain null hypersurface $\mathcal{N}_f^{n+1}$ in $M^{n+2}_1$ and $f$ has a locally…

Differential Geometry · Mathematics 2025-06-10 Riku Kishida

The condition for pressure isotropy is reduced to a recurrence equation with variable, rational coefficients of order three. We prove that this difference equation can be solved in general. Consequently we can find an exact solution to the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. J. John , S. D. Maharaj

The Gaussian polytope $\mathcal P_{n,d}$ is the convex hull of $n$ independent standard normally distributed points in $\mathbb R^d$. We derive explicit expressions for the probability that $\mathcal P_{n,d}$ contains a fixed point…

Probability · Mathematics 2019-12-30 Zakhar Kabluchko , Dmitry Zaporozhets

Motivated by the recent suggestions that very massive pulsar (PSR J0952-0607) and very light compact object (HESS J1731-347) exist, in this article, we revisit the possibility of such objects being strange stars instead of the standard…

High Energy Astrophysical Phenomena · Physics 2023-09-06 H. C. Das , Luiz L. Lopes

Pressure isotropy, i.e., equality between radial and tangential pressure, is often assumed when studying neutron stars. However, mechanisms such as pion/kaon condensation, magnetic fields, and dark matter clustering can lead to pressure…

High Energy Astrophysical Phenomena · Physics 2026-03-16 Peter T. H. Pang , Stephanie M. Brown , Thibeau Wouters , Chris Van Den Broeck

The possibility of a neutron m=2-superfluid in the interior of neutron stars is investigated. This pairing state is energetically favoured in strong magnetic fields ($H\sim 10^{16}-10^{17}$ G). Because of the node in the angular-dependent…

Astrophysics · Physics 2016-08-30 Ch. Schaab , F. Weber , M. K. Weigel

We present a closed analytical formula for the scattering intensity from charged hard sphere fluids with any arbitrary number of components. Our result is an extension to ionic systems of Vrij's analogous expression for uncharged hard…

Statistical Mechanics · Physics 2009-10-30 Domenico Gazzillo , Achille Giacometti , Flavio Carsughi
‹ Prev 1 8 9 10 Next ›