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Related papers: Reconstruction of Scalar Potentials in Modified Gr…

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In this paper, we explore the nature of scalar field potential in $f(R, R_{\alpha\beta} R^{\alpha\beta},\phi)$ gravity using a well-motivated reconstruction scheme for flat FRW geometry. The beauty of this scheme lies in the assumption that…

General Relativity and Quantum Cosmology · Physics 2017-01-25 M. Zubair , Farzana Kousar , Saira Waheed

The present study investigates the nature of the field potential via new technique known as reconstruction method for the scalar field potentials. The key point of this technique is the assumption that Hubble parameter is dependent on the…

General Relativity and Quantum Cosmology · Physics 2013-10-14 M. Sharif , Saira Waheed

We develop a technique for the reconstruction of the potential for a scalar field in cosmological models based on induced gravity. The potentials reproducing cosmological evolutions driven by barotropic perfect fluids, a cosmological…

General Relativity and Quantum Cosmology · Physics 2012-05-10 Alexander Y. Kamenshchik , Alessandro Tronconi , Giovanni Venturi

We develop a technique for the reconstruction of the potential for a scalar field or a tachyon field, reproducing a given cosmological evolution in a closed and open isotropic cosmological models. Such potentials are explicitly written down…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Alexander Y. Kamenshchik , Serena Manti

We consider the Chiral Cosmological Models (CCMs) and modified gravity theories associated with them. Generalization of the superpotential method for a general CCM with several scalar fields is performed, and the method of construction CCMs…

General Relativity and Quantum Cosmology · Physics 2019-09-25 S. V. Chervon , I. V. Fomin , E. O. Pozdeeva , M. Sami , S. Yu. Vernov

The accelerated expansion of the universe has been widely confirmed, posing challenges to the standard $\Lambda$CDM model, particularly the cosmological coincidence problem. This has motivated the exploration of modified gravity theories,…

General Relativity and Quantum Cosmology · Physics 2025-01-03 Gaurav N. Gadbail , Sanjay Mandal , P. K. Sahoo , Kazuharu Bamba

We study the cosmological evolution of the field equations in the context of Einstein-Aether cosmology by including a scalar field in a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker spacetime. Our analysis is separated into two…

General Relativity and Quantum Cosmology · Physics 2020-01-17 Andronikos Paliathanasis , G. Papagiannopoulos , Spyros Basilakos , John D. Barrow

We describe how to reconstruct generalized scalar-tensor gravity (GSTG) theory, which admits exact solutions for physical type of the potentials. Our consideration deals with cosmological inflationary models based on GSTG with non-minimal…

General Relativity and Quantum Cosmology · Physics 2020-05-20 I. V. Fomin , S. V. Chervon , A. V. Tsyganov

We explore dynamics of cosmological models with bounce solutions evolving on a spatially flat Friedmann-Lemaitre-Robertson-Walker background. We consider cosmological models that contain the Hilbert-Einstein curvature term, the induced…

General Relativity and Quantum Cosmology · Physics 2016-12-08 Ekaterina O. Pozdeeva , Maria A. Skugoreva , Alexey V. Toporensky , Sergey Yu. Vernov

A nonlocal gravity model is considered which does not assume the existence of a new dimensional parameter in the action and includes a function $f(\Box^{-1} R)$, with $\Box$ the d'Alembertian operator. Using a reconstruction procedure for…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-06 E. Elizalde , E. O. Pozdeeva , S. Yu. Vernov

Recent cosmological observations, including the latest Dark Energy Spectroscopic Instrument (DESI) data releases DR1 and DR2, have renewed interest in the possibility that dark energy may exhibit dynamical behavior rather than being a…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-07 Redouane El Ouardi , Amine Bouali , Ahmed Errahmani , Ryan E. Keeley , Arman Shafieloo , Taoufik Ouali

In this work, we use reconstruction methods to obtain cosmological solutions in the recently developed scalar-tensor representation of $f(R,T)$ gravity. Assuming that matter is described by an isotropic perfect fluid and the spacetime is…

General Relativity and Quantum Cosmology · Physics 2022-03-15 Tiago B. Gonçalves , João Luís Rosa , Francisco S. N. Lobo

This paper treats nonrelativistic matter and a scalar field $\phi$ with a monotonically decreasing potential minimally coupled to gravity in flat Friedmann-Lema\^{i}tre-Robertson-Walker cosmology. The field equations are reformulated as a…

General Relativity and Quantum Cosmology · Physics 2015-11-11 Artur Alho , Claes Uggla

We study cosmology in scalar-tensor (Bergmann Wagoner) gravity, restricting the coupling function, ${\omega}({\phi})$ to be constant. Rather than specify the form of the cosmological function, ${\lambda}({\phi})$, the scalar field is…

General Relativity and Quantum Cosmology · Physics 2017-02-16 Anderson Mendonça da Silva , Jim E. F. Skea

The purpose of this work is to use a renormalized quantum scalar field to investigate very early cosmology, in the Planck era immediately following the big bang. Renormalization effects make the field potential dependent on length scale,…

General Relativity and Quantum Cosmology · Physics 2012-07-16 Kerson Huang , Hwee-Boon Low , Roh-Suan Tung

We study the procedure of the reconstruction of phantom-scalar field potentials in two-field cosmological models. It is shown that while in the one-field case the chosen cosmological evolution defines uniquely the form of the scalar…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alexander A. Andrianov , Francesco Cannata , Alexander Y. Kamenshchik , Daniele Regoli

A linear relationship between the Hubble expansion parameter and the time derivative of the scalar field is assumed in order to derive exact analytic cosmological solutions to Einstein's gravity with two fluids: a barotropic perfect fluid…

General Relativity and Quantum Cosmology · Physics 2009-09-29 Olga Arias , Tame Gonzalez , Israel Quiros

The reconstruction of f(R)-gravity is showed by using an auxiliary scalar field in the context of cosmological evolution, this development provide a way of reconstruct the form of the function f (R) for a given evolution of the Hubble…

High Energy Physics - Theory · Physics 2009-07-22 Diego Sáez-Gómez

The conditions under which cosmologies driven by time varying cosmological terms can be described by a scalar field coupled to a perfect fluid are discussed. An algorithm to reconstruct potentials dynamically and thermodynamically analogue…

Astrophysics · Physics 2009-11-07 J. M. F. Maia , J. A. S. Lima

We present the data-driven reconstruction of gravitational theories and Dark Energy models on cosmological scales. We showcase the power of present cosmological probes at constraining these models and quantify the knowledge of their…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-22 Marco Raveri
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