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Related papers: Modified gravity for surveys

200 papers

We present an updated and improved equation of state (which we call the NDL EoS) for use in neutron-star structure and supernova simulations. This EoS is based upon a framework originally developed by Bowers & Wilson, but there are numerous…

High Energy Astrophysical Phenomena · Physics 2013-03-04 Matthew Meixner , J. Pocahontas Olson , Grant Mathews , N. Q. Lan , H. E. Dalhed

This paper highlights cosmologically viable sine and cosine hyperbolic evolution functions in the framework of $f(Q,\mathcal{L}_m)$ gravity. The models have been tested to check the behavior of the equation of state (EoS) parameter under…

General Relativity and Quantum Cosmology · Physics 2026-02-02 V. A. Kshirsagar , S. A. Kadam , Vishwajeet S. Goswami

Determining the mechanism behind the current cosmic acceleration constitutes a major question nowadays in theoretical physics. If the dark energy route is taken, this problem may potentially bring to light new insights not only in Cosmology…

Astrophysics · Physics 2009-07-09 E. M. Barboza , J. S. Alcaniz

The parametrized equation of state (EOS) of neutron stars is investigated by Bayesian inference method with various constraints from both nuclear physics and modern astronomical observations. The expansion coefficients correspond to the…

Nuclear Theory · Physics 2025-09-04 Xieyuan Dong , Hong Shen , Jinniu Hu , Ying Zhang

This study investigates the cosmological implications of $f(R,\Sigma,T)$ gravity by reconstructing the Hubble parameter from a logarithmic parameterization of the $O_m(z)$ diagnostic. Our approach offers a model-independent way to probe the…

General Relativity and Quantum Cosmology · Physics 2026-05-12 N. Myrzakulov , Anirudh Pradhan , Anil Kumar Yadav , S. H. Shekh

In the present paper we study the oscillations of fast rotating neutron stars with realistic equations of state (EoS) within the Cowling approximation. We derive improved empirical relations for gravitational wave asteroseismology with…

Solar and Stellar Astrophysics · Physics 2013-09-04 Daniela D. Doneva , Erich Gaertig , Kostas D. Kokkotas , Christian Krüger

Despite its elegance, the theory of General Relativity is subject to experimental, observational, and theoretical scrutiny to arrive at tighter constraints or an alternative, more preferred theory. In alternative gravity theories, the…

General Relativity and Quantum Cosmology · Physics 2023-09-12 Bhaskar Biswas , Evangelos Smyrniotis , Ioannis Liodis , Nikolaos Stergioulas

In astrophysics as well as in hadron physics progress has recently been made on the determination of the hadronic equation of state (EOS) of compressed matter. The results are contradictory, however. Simulations of heavy ion reactions are…

Nuclear Theory · Physics 2009-11-11 Ch. Hartnack , H. Oeschler , Jörg Aichelin

In this work we present a detailed explanation of the construction of an appropriate equation of state (EoS) for nuclear astrophysics. We use a relativistic model in order to obtain an EoS for neutrally charged matter that extends from very…

Astrophysics · Physics 2007-05-23 D. P. Menezes , C. Providencia

This paper is a parametrization of the equation of state (EoS) parameter of dark energy (DE), which is parameterized using Square-Root (SR) form i.e. $\omega _{SR}=\text{$\omega _{0}$}+\text{$\omega _{1}$}\frac{z}{\sqrt{z^{2}+1}}$, where…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-01 M. Koussour , N. Myrzakulov , Alnadhief H. A. Alfedeel , E. I. Hassan , D. Sofuoğlu , Safa M. Mirgani

Modified theories of gravity encompass a class of $f(R)$-models that seek to elucidate the observed late time accelerated expansion of the universe. In this study, we examine a set of viable $f(R)$ models (Hu-Sawicki: two cases,…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-15 Kumar Ravi , Anirban Chatterjee , Biswajit Jana , Abhijit Bandyopadhyay

We present a novel reconstruction method of $f(T)$ teleparallel gravity from phenomenological parameterizations of the deceleration parameter or other alternatives. This can be used as a toolkit to produce viable modified gravity scenarios…

General Relativity and Quantum Cosmology · Physics 2019-10-29 W. El Hanafy , G. G. L. Nashed

We contribute a publicly available set of tables and code to provide Equations of State (EoS) for matter at neutron star densities. Our EoSes are constrained only by input from hadron physics and fundamental principles, without feedback…

General Relativity and Quantum Cosmology · Physics 2021-03-24 Eva Lope Oter , Andreas Windisch , Felipe J. Llanes-Estrada , Mark Alford

The equation of state (EoS) of the neutron star (NS) matter remains an enigma. In this work we perform the Bayesian parameter inference with the gravitational wave data (GW170817) and mass-radius observations of some NSs (PSR J0030+0451,…

High Energy Astrophysical Phenomena · Physics 2021-03-23 Shao-Peng Tang , Jin-Liang Jiang , Wei-Hong Gao , Yi-Zhong Fan , Da-Ming Wei

In this article, we attempt to describe cosmic late-time acceleration of the universe in the framework of $f(R,L_m)$ gravity by using an effective equation of state when the account is taken of bulk viscosity. We presume a non-linear…

General Relativity and Quantum Cosmology · Physics 2023-03-31 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , Pradyumn Kumar Sahoo

Bayesian hierarchical inference of phenomenological parameterized neutron star equations of state (EoS) from multiple gravitational wave observations of binary neutron star mergers is of fundamental importance in improving our understanding…

General Relativity and Quantum Cosmology · Physics 2023-03-08 Anarya Ray , Michael Camilo , Jolien Creighton , Shaon Ghosh , Soichiro Morisaki

A new scheme for testing nuclear matter equations of state (EsoS) at high densities using constraints from neutron star phenomenology and a flow data analysis of heavy-ion collisions is suggested. An acceptable EoS shall not allow the…

One of the central challenges in modern cosmology is understanding the nature of dark energy and its evolution throughout the history of the Universe. Dark energy is commonly modeled as a perfect fluid with a time-varying equation-of-state…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-26 Samsuzzaman Afroz , Suvodip Mukherjee

Since the late 1990's observations of type Ia Supernova, our universe is predicted to experience a late time cosmic acceleration. Theoretical support to this observation were intended to be built via proposition of a hypothetical fluid…

General Relativity and Quantum Cosmology · Physics 2020-08-10 Promila Biswas , Parthajit Roy , Ritabrata Biswas

We develop a new nonparametric method to reconstruct the Equation of State (EoS) of Neutron Star with multimessenger data. As an universal function approximator, the Feed-Forward Neural Network (FFNN) with one hidden layer and a sigmoidal…

High Energy Physics - Phenomenology · Physics 2023-06-16 Ming-Zhe Han , Jin-Liang Jiang , Shao-Peng Tang , Yi-Zhong Fan