English
Related papers

Related papers: Gravitational antiscreening in stellar interiors

200 papers

The problem of the enormous gravitational effects observed by the astronomers in several galactic nuclei with obscure bodies appears puzzling. These bodies are too large to be neutron stars generated by supernovae of primeval stars and are…

General Physics · Physics 2007-05-23 Maurizio Michelini

The dynamics of a self-gravitating neutron gas in presence of a magnetic field is being studied taking the equation of state of a magnetized neutron gas obtained in a previous study [2]. We work in a Bianchi I spacetime characterized by a…

Astrophysics · Physics 2008-10-15 D. Manreza Paret

In recent years, there have been several successful attempts to constrain the equation of state of neutron star matter using input from low-energy nuclear physics and observational data. We demonstrate that significant further restrictions…

High Energy Astrophysical Phenomena · Physics 2014-06-25 Aleksi Kurkela , Eduardo S. Fraga , Jurgen Schaffner-Bielich , Aleksi Vuorinen

We calculate the quantum corrections to the Newtonian potential induced by a massless, nonminimally coupled scalar field on Minkowski background. We make use of the graviton vacuum polarization calculated in our previous work and solve the…

High Energy Physics - Theory · Physics 2013-09-02 Anja Marunovic , Tomislav Prokopec

The effects that the structure of a neutron star would have on the gravitational emission of a binary system are studied in a perturbative regime, and in the frequency domain. Assuming that a neutron star is perturbed by a point mass moving…

General Relativity and Quantum Cosmology · Physics 2011-07-19 J. A. Pons , E. Berti , L. Gualtieri , G. Miniutti , V. Ferrari

Gravitationally bound neutrons have become an important tool in the experimental searches for new physics, such as modifications to Newton's force or candidates for dark matter particles. Here we include the relativistic effects of…

Quantum Physics · Physics 2022-11-23 Germain Tobar , Simon Haine , Fabio Costa , Magdalena Zych

We study magnetospheric structure surrounding rotating magnetized neutron star with nonvanishing NUT (Newman-Tamburino-Unti) parameter. For the simplicity of calculations Goldreich-Julian charge density is analyzed for the aligned neutron…

Astrophysics · Physics 2009-11-13 V. S. Morozova , B. J. Ahmedov , V. G. Kagramanova

In the present paper we investigate self-consistently slowly rotating neutron and strange stars in R-squared gravity. For this purpose we first derive the equations describing the structure of the slowly rotating compact stars in…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Kalin V. Staykov , Daniela D. Doneva , Stoytcho S. Yazadjiev , Kostas D. Kokkotas

We carry out a simple analysis of (n+3)-dimensional gravity in the context of recent work on 'large' supplementary dimensions and deduce a formula for the expected compactification radius for the n additional dimensions in the universe, as…

Nuclear Theory · Physics 2010-11-19 Alejandro Frank , Piet van Isacker , Joaquin Gomez-Camacho

We consider an extension of the recent experiment with ultracold neutrons and the quantization of its vertical motion in order to test the Weak Equivalence Principle. We show that an improvement on the energy resolution of the experiment…

High Energy Physics - Phenomenology · Physics 2017-08-23 O. Bertolami , F. M. Nunes

There are well-known problems associated with the idea of (local) gravitational energy in general relativity. We offer a new perspective on those problems by comparison with Newtonian gravitation, and particularly geometrized Newtonian…

History and Philosophy of Physics · Physics 2018-04-18 Neil Dewar , James Owen Weatherall

Neutron stars are compact objects rotating at high speed, up to a substantial fraction of the speed of light (up to 20\% for millisecond pulsars) and possessing ultra-strong electromagnetic fields (close to and sometimes above the quantum…

High Energy Astrophysical Phenomena · Physics 2020-01-13 Jérôme Pétri

The detection of an electromagnetic counterpart (GRB 170817A) to the gravitational wave signal (GW170817) from the merger of two neutron stars opens a completely new arena for testing theories of gravity. We show that this measurement…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-27 Tessa Baker , Emilio Bellini , Pedro G. Ferreira , Macarena Lagos , Johannes Noller , Ignacy Sawicki

We construct parameter sets of the relativistic mean-field model fitted to the recent constraints on the asymmetry energy $J$ and the slope parameter $L$ for pure neutron matter. We find cases of unphysical behaviour, i.e.\ the appearance…

High Energy Astrophysical Phenomena · Physics 2018-12-19 Nadine Hornick , Laura Tolos , Andreas Zacchi , Jan-Erik Christian , Jürgen Schaffner-Bielich

We study the bound on the compactness of a stellar object in pure Lovelock theories of arbitrary order in arbitrary spacetime dimensions, involving electromagnetic field. The bound we derive for a generic pure Lovelock theory, reproduces…

General Relativity and Quantum Cosmology · Physics 2020-07-06 Sumanta Chakraborty , Naresh Dadhich

We study the structure of neutron stars in scalar-tensor theories for the nonminimal coupling of the form $(1+\kappa \xi \phi^{2})\cal R$. We solve the hydrostatic equilibrium equations for two different types of scalar field potentials and…

General Relativity and Quantum Cosmology · Physics 2019-04-02 A. Savaş Arapoğlu , K. Yavuz Ekşi , A. Emrah Yükselci

$f(R)$ theories of gravity are one of the most popular alternative explanations for dark energy and therefore studying the possible astrophysical implications of these theories is an important task. In the present paper we make a…

General Relativity and Quantum Cosmology · Physics 2015-06-23 Stoytcho S. Yazadjiev , Daniela D. Doneva , Kostas D. Kokkotas

We study how light scalar fields can change the stellar landscape by triggering a new phase of nuclear matter. Scalars coupled to nucleons can develop a non-trivial expectation value at finite baryon density. This sourcing of a scalar…

High Energy Physics - Phenomenology · Physics 2023-07-28 Reuven Balkin , Javi Serra , Konstantin Springmann , Stefan Stelzl , Andreas Weiler

Binary pulsar observations and gravitational wave detections seriously constrained scalar-tensor theories with massless scalar field allowing only small deviations from general relativity. If we consider a nonzero mass of the scalar field,…

General Relativity and Quantum Cosmology · Physics 2018-08-15 Kalin V. Staykov , Dimitar Popchev , Daniela D. Doneva , Stoytcho S. Yazadjiev

We study the effects of strong magnetic fields on the neutron star structure. If the interior field of a star is on the same order of the surface field currently observed, the influences of the magnetic field on the star mass and radius are…

Astrophysics · Physics 2014-10-13 Guangjun Mao , Akira Iwamoto , Zhuxia Li