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Related papers: Dark stars in Starobinsky's model

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We consider galaxy halos formed by dark matter bosons with mass in the range of about a few tens or hundreds eV. A major part of the particles is in a noncondensed state and described under the Thomas-Fermi approach. Derived equations are…

Astrophysics of Galaxies · Physics 2021-12-08 Iskander G. Abdullin , Vladimir A. Popov

We calculate the extent to which collisionless dark matter impacts the stability of supermassive stars $(M\gtrsim10^4\,M_\odot)$. We find that, depending on the star's mass, a dark matter content in excess of ${\sim}1\%$ by mass throughout…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-24 Kyle S. Kehrer , George M. Fuller

We review our recent results on dark matter from Starobinsky supergravity. In this context, a natural candidate for Cold Dark Matter is the gravitino. On the other hand, assuming the supersymmetry broken at scales much higher than the…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Andrea Addazi , Maxim Yu. Khlopov

As is well known, the gravitational degrees of freedom contained in $R+\zeta R^{2}$ (super)gravity lead to Starobinsky's potential, in a one-field setting for inflationary Cosmology that appears favored by Planck data. In this letter we…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Andrea Addazi , Maxim Yu. Khlopov

We study the coupling of nuclear matter described by the BPS Skyrme model to generalized gravity. Concretely, we consider the Starobinsky model which provides the leading-order correction to the Einstein-Hilbert action. Static solutions…

High Energy Physics - Theory · Physics 2020-09-02 C. Adam , M. Huidobro , R. Vazquez , A. Wereszczynski

In this work, the collapsing process of a spherically symmetric star, made of dust cloud, is studied in Ho\v{r}ava Lifshitz gravity in the background of Chaplygin gas dark energy. Two different classes of Chaplygin gas, namely, New variable…

General Physics · Physics 2014-05-30 Prabir Rudra , Ujjal Debnath

Stability of supermassive stars embedded in hot dark matter is investigated on the base of the energetic method. Stability effect of dark mater is compared with rotational stabilization and preference of the last factor is advocated.

Astrophysics · Physics 2009-10-30 G. S. Bisnovatyi-Kogan

We analyze the observed properties of dwarf galaxies, which are dark matter dominated astrophysical objects, by assuming that dark matter is in the form of a strongly - coupled, dilute Bose - Einstein condensate. The basic astrophysical…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-02 T. Harko

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

One of the stiffest equations of state for matter in a compact star is constant energy density and this generates the interior Schwarzschild radius to mass relation and the Misner maximum mass for relativistic compact stars. If dark matter…

Solar and Stellar Astrophysics · Physics 2016-03-25 José P. S. Lemos , Francisco J. Lopes , Gonçalo Quinta , Vilson T. Zanchin

Fuzzy dark matter (FDM), a practical alternative to cold dark matter, can exist in compact stars. Here, applying the FDM equation of state (EoS) constrained by CMB and large-scale structure data, we calculate the structure of relativistic…

High Energy Astrophysical Phenomena · Physics 2025-10-08 Zeinab Rezaei

Rotating bosonic dark matter halos are considered as potential candidates for modeling dark matter in galactic halos. These bosonic dark matter halos can be viewed as a dilute and very extended version of bosonic stars, and the methods used…

Astrophysics of Galaxies · Physics 2025-03-13 Jorge Castelo Mourelle , Christoph Adam

We analyze the possibility that due to their superfluid properties some compact astrophysical objects may contain a significant part of their matter in the form of a Bose-Einstein condensate. To study the condensate we use the…

Solar and Stellar Astrophysics · Physics 2013-05-30 P. H. Chavanis , T. Harko

We review various modified gravities considered as gravitational alternative for dark energy. Specifically, we consider the versions of $f(R)$, $f(G)$ or $f(R,G)$ gravity, model with non-linear gravitational coupling or string-inspired…

High Energy Physics - Theory · Physics 2009-09-17 S. Nojiri , S. D. Odintsov

In this work, we use power-law cosmology to investigate the evolution of black holes within the context of metric $f(R)$ gravity satisfying the conditions provided by Starobinsky model. In our study, it is observed that presently…

General Relativity and Quantum Cosmology · Physics 2020-10-13 Suraj Kumar Pati , Bibekananda Nayak , Lambodar Prasad Singh

We analyse configurations of compact stars in the so-called R-squared gravity in the Palatini formalism. Using a realistic equation of state we show that the mass-radius configurations are lighter than their counterparts in General…

General Relativity and Quantum Cosmology · Physics 2016-12-28 F. A. Teppa Pannia , F. García , S. E. Perez Bergliaffa , M. Orellana , G. E. Romero

All $f(R)$ modified gravity theories are conformally identical to models of quintessence in which matter is coupled to dark energy with a strong coupling. This coupling induces a cosmological evolution radically different from standard…

Astrophysics · Physics 2008-11-26 Luca Amendola , David Polarski , Shinji Tsujikawa

In this paper, we study the slowly rotating neutron stars in $f(R, T)$ gravity based on Hartle-Thorne formalism. We first consider the simplest matter-geometry coupled modified gravity, namely $f(R, T)=R+2\chi T$. We compute the mass,…

General Relativity and Quantum Cosmology · Physics 2024-09-16 Masum Murshid , Mehedi Kalam

There is a growing interest in investigating modified theories of gravity, primarily, with the aim of explaining the universe's accelerated expansion, which has been confirmed by several independent observations. Compact objects, like…

General Relativity and Quantum Cosmology · Physics 2021-08-16 K Nobleson , Tuhin Malik , Sarmistha Banik

We investigate the application of an equation of state that incorporates corrections derived from the Snyder model (and the Generalized Uncertainty Principle) to describe the behavior of matter in a low-mass star. Remarkably, the resulting…

General Relativity and Quantum Cosmology · Physics 2023-12-05 Anna Pachoł , Aneta Wojnar