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相关论文: White dwarfs in regularized 4D Einstein-Gauss-Bonn…

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An alternative theory of gravity that has attracted much attention recently is the novel four-dimensional Einstein-Gauss-Bonnet (4D EGB) gravity. The theory is rescaled by the Gauss-Bonnet (GB) coupling constant $\alpha \rightarrow…

广义相对论与量子宇宙学 · 物理学 2022-03-25 Khadije Jafarzade , Mahdi Kord Zangeneh , Francisco S. N. Lobo

We study the cosmology of a specific class of nonlocal model of modified gravity, the so-called Deser-Woodard (DW) model, modifying the Einstein-Hilbert action by a term $\sim R f(\Box^{-1}R)$, where $f$ is a free function. Choosing $f$ so…

宇宙学与河外天体物理 · 物理学 2019-04-18 Luca Amendola , Yves Dirian , Henrik Nersisyan , Sohyun Park

After the prediction of many sub- and super-Chandrasekhar (at least a dozen for the latter) limiting mass white dwarfs, hence apparently peculiar class of white dwarfs, from the observations of luminosity of type Ia supernovae, researchers…

高能天体物理现象 · 物理学 2021-03-09 Surajit Kalita , Banibrata Mukhopadhyay

Recently, a non-trivial $4D$ Einstein-Gauss-Bonnet (EGB) theory of gravity, by rescaling the GB coupling parameter as $\alpha/(D-4)$, was formulated in \cite{Glavan:2019inb}, which bypasses Lovelock's theorem and avoids Ostrogradsky…

广义相对论与量子宇宙学 · 物理学 2020-09-17 Shafqat Ul Islam , Rahul Kumar , Sushant G. Ghosh

In this work, we investigate the equilibrium configurations of massive white dwarfs (MWD) in the context of modified gravity, namely $f(R,L_m)$ gravity, where $R$ stands for the Ricci scalar and $L_m$ is the Lagrangian matter density. We…

广义相对论与量子宇宙学 · 物理学 2022-06-22 R. V. Lobato , G. A. Carvalho , N. G. Kelkar , M. Nowakowski

The advancement of astronomical observations opens the possibility of testing our current understanding of gravitational theory in the strong-field regime and probing any deviation from general relativity. We explore to what extent compact…

广义相对论与量子宇宙学 · 物理学 2024-03-29 M. D. Danarianto , I. Prasetyo , A. Suroso , B. E. Gunara , A. Sulaksono

This thesis investigates compact astrophysical objects within modified theories of gravity, focusing on neutron stars and strange stars. The work studies their internal structure, equilibrium, and stability in gravitational frameworks based…

广义相对论与量子宇宙学 · 物理学 2026-05-26 Sneha Pradhan

We investigate the radial density distribution of the dynamical dark energy inside the white dwarfs (WDs) and its possible impact on their intrinsic structure. The minimally-coupled dark energy with barotropic equation of state which has…

宇宙学与河外天体物理 · 物理学 2020-01-08 Sviatoslav Smerechynskyi , Maksym Tsizh , Bohdan Novosyadlyj

The mass-radius relations for white dwarf stars are investigated by solving the Newtonian as well as Tolman-Oppenheimer-Volkoff (TOV) equations for hydrostatic equilibrium assuming the electron gas to be non-interacting. We find that the…

太阳与恒星天体物理 · 物理学 2017-11-07 Arun Mathew , Malay K. Nandy

The properties of uniformly rotating white dwarfs (RWDs) are analyzed within the framework of Newton's gravity and general relativity. In both cases Hartle's formalism is applied to construct the internal and external solutions to the field…

太阳与恒星天体物理 · 物理学 2015-03-16 Kuantay Boshkayev , Jorge A. Rueda , Remo Ruffini , Ivan Siutsou

Recently, a novel Einstein-Gauss-Bonnet gravity in four dimensions has been introduced [Phys. Rev. Lett. 124 (2020) 081301]. We will investigate cosmological consequences of this model in details. We will consider linear matter density…

广义相对论与量子宇宙学 · 物理学 2020-10-05 Zahra Haghani

We explore the potential variation of two fundamental constants, the fine-structure constant $\alpha$ and the proton-to-electron mass ratio $\mu$, within the framework of modified gravity theories and finite-temperature effects. Utilising…

太阳与恒星天体物理 · 物理学 2025-09-17 Akhil Uniyal , Surajit Kalita , Yosuke Mizuno , Sayan Chakrabarti , Yan Lu

White dwarfs, one of the compact objects in the universe, play a crucial role in astrophysical research and provide a platform for exploring nuclear physics. In this work, we extend the relativistic mean field approach by using a…

核理论 · 物理学 2025-08-18 Ling-Jun Guo , Yao Ma , Yong-Liang Ma , Ruo-Xi Wu , Yue-Liang Wu

The existence of strange matter in compact stars may pose striking sequels of the various physical phenomena. As an alternative to neutron stars, a new class of compact stars called strange stars should exist if the strange matter…

广义相对论与量子宇宙学 · 物理学 2021-03-02 Ayan Banerjee , Takol Tangphati , Phongpichit Channuie

In this work we investigate the structure of white dwarfs using the Tolman-Oppenheimer-Volkoff equations and compare our results with those obtained from Newtonian equations of gravitation in order to put in evidence the importance of…

广义相对论与量子宇宙学 · 物理学 2018-03-28 G. A. Carvalho , R. M. Marinho , M. Malheiro

Generally the virial theorem provides a relation between various components of energy integrated over a system. This helps us to understand the underlying equilibrium. Based on the virial theorem we can estimate, for example, the maximum…

太阳与恒星天体物理 · 物理学 2020-10-21 Banibrata Mukhopadhyay , Arnab Sarkar , Christopher A. Tout

Theories that attempt to unify the four fundamental interactions and alternative theories of gravity predict time and/or spatial variation of the fundamental constants of nature. Different versions of these theories predict different…

宇宙学与河外天体物理 · 物理学 2020-10-14 Susana J. Landau

In this work we study the properties of compact spheres made of a charged perfect fluid with a MIT bag model EoS for quark matter. Considering static spherically symmetric spacetime we derive the hydrostatic equilibrium equations in the…

广义相对论与量子宇宙学 · 物理学 2022-03-01 Juan M. Z. Pretel , Ayan Banerjee , Anirudh Pradhan

Since the derivation of a well-defined $D\to4$ limit for 4D Einstein-Gauss-Bonnet (4DEGB) gravity coupled to a scalar field, there has been considerable interest in testing it as an alternative to Einstein's general theory of relativity.…

广义相对论与量子宇宙学 · 物理学 2025-04-25 Alejandro Saavedra , Octavio Fierro , Michael Gammon , Robert B. Mann , Guillermo Rubilar

Recently, there has been significant interest regarding the regularization of a $D\rightarrow 4$ limit of Einstein-Gauss-Bonnet (EGB) gravity. This regularization involves re-scaling the Gauss-Bonnet (GB) coupling constant as…

广义相对论与量子宇宙学 · 物理学 2024-08-14 Zinnat Hassan , P. K. Sahoo