English
Related papers

Related papers: What $\xi$? Cosmological constraints on the non-mi…

200 papers

Dynamical systems methods are used to investigate dynamics of a flat Friedmann-Robertson-Walker cosmological model with the non-minimally coupled scalar field and a potential function. Performed analysis distinguishes the value of…

General Relativity and Quantum Cosmology · Physics 2020-09-07 Orest Hrycyna

Quantum cosmology is investigated in a de Sitter minisuperspace model with a quantized scalar field non-minimally coupled to curvature. Quantum states of the scalar field must satisfy the regularity condition, which requires that the…

General Relativity and Quantum Cosmology · Physics 2019-08-21 Shao-Jiang Wang , Masaki Yamada , Alexander Vilenkin

In this publication we investigate dynamics of a flat FRW cosmological model with a non-minimally coupled scalar field with the coupling term $\xi R \psi^{2}$ in the scalar field action. The quadratic potential function $V(\psi)\propto…

High Energy Physics - Theory · Physics 2009-05-06 Orest Hrycyna , Marek Szydlowski

Dynamical systems methods are used to investigate cosmological model with non-minimally coupled scalar field. Existence of an asymptotically unstable de Sitter state distinguishes values of the non-minimal coupling constant parameter…

General Relativity and Quantum Cosmology · Physics 2017-05-31 Orest Hrycyna

Dynamical systems methods are used to investigate global behavior of the spatially flat Friedmann-Robertson-Walker cosmological model in gravitational theory with a non-minimally coupled scalar field and a constant potential function. We…

General Relativity and Quantum Cosmology · Physics 2015-11-11 Orest Hrycyna , Marek Szydlowski

We consider a universe with a positive effective cosmological constant and a nonminimally coupled scalar field. When the coupling constant is negative, the scalar field exhibits linear growth at asymptotically late times, resulting in a…

General Relativity and Quantum Cosmology · Physics 2015-04-06 Dražen Glavan , Tomislav Prokopec

We study the minimally and non-minimally coupled scalar field models as possible alternatives for dark energy, the mysterious energy component that is driving the accelerated expansion of the universe. After discussing the dynamics at both…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Zahra Davari , Valerio Marra , Mohammad Malekjani

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

We explore dynamics of cosmological models with a nonminimally coupled scalar field evolving on a spatially flat Friedmann-Lemaitre-Robertson-Walker background. We consider cosmological models including the Hilbert-Einstein curvature term…

General Relativity and Quantum Cosmology · Physics 2014-10-01 Maria A. Skugoreva , Alexey V. Toporensky , Sergey Yu. Vernov

We study scaling symmetry in a class of non-minimally coupled scalar field in a background of Friedmann-Robertson-Walker (FRW) spacetime. We use a non-minimally coupling $R L^{(\varphi)}$. We find the corresponding conserved charge of that…

General Physics · Physics 2023-12-25 Malik Al Matwi

This paper explores cosmological scenarios in a scalar-tensor theory of gravity, including both a non-minimal coupling with scalar curvature of the form $R\phi^2$ and a non-minimal derivative coupling of the form…

General Relativity and Quantum Cosmology · Physics 2025-10-13 Ravil R. Fatykhov , Sergey V. Sushkov

We investigate observational constraints on a specific one-parameter extension to the minimal quintessence model, where the quintessence field acquires a quadratic coupling to the scalar curvature through a coupling constant $\xi$. The…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-28 Chao-Qiang Geng , Chung-Chi Lee , Yi-Peng Wu

We investigate isotropic and homogeneous cosmological scenarios in the scalar-tensor theory of gravity with non-minimal derivative coupling of a scalar field to the curvature given by the term $(\zeta/H_0^2) G^{\mu\nu}\nabla_\mu\phi…

General Relativity and Quantum Cosmology · Physics 2023-06-02 Sergey V. Sushkov , Rafkat Galeev

We consider cosmological dynamics in the theory of gravity with the scalar field possessing the nonminimal kinetic coupling to curvature given as $\kappa G^{\mu\nu}\phi_{,\mu}\phi_{,\nu}$, and the Higgs-like potential…

General Relativity and Quantum Cosmology · Physics 2017-09-18 Jiro Matsumoto , Sergey V. Sushkov

We investigate the cosmological dynamics of non-minimally coupled scalar field system described by $F(\phi)R$ coupling with $F(\phi)=(1-\xi\phi^N)R$($N\ge2$) and the field potential, $V(\phi)=V_0\phi^n$. We use a generic set of dynamical…

High Energy Physics - Theory · Physics 2013-05-30 M. Sami , M. Shahalam , M. Skugoreva , A. Toporensky

We provide further evidence that a massless cosmological scalar field with a non-minimal coupling to the Ricci curvature of the type $M^2_{\rm pl}(1+\xi \sigma^n/M_{\rm pl}^n) $ alleviates the existing tension between local measurements of…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 Matteo Braglia , Mario Ballardini , William T. Emond , Fabio Finelli , A. Emir Gumrukcuoglu , Kazuya Koyama , Daniela Paoletti

We discuss the cosmological implications of the string swampland conjectures for late-time cosmology, and test them against a wide range of state of the art cosmological observations. The refined de Sitter conjecture constrains either the…

High Energy Physics - Theory · Physics 2019-04-24 Marco Raveri , Wayne Hu , Savdeep Sethi

In this letter, cosmology of a simple NMDC gravity with $\xi R \phi_{,\mu}\phi^{,\mu}$ term and a free kinetic term is considered in flat geometry and in presence of dust matter. A logarithm field transformation $\phi' = \mu \ln \phi$ is…

General Relativity and Quantum Cosmology · Physics 2017-08-22 Burin Gumjudpai , Yuttana Jawralee , Narakorn Kaewkhao

We study dynamics of non-minimally coupled scalar field cosmological models with Higgs-like potentials and a negative cosmological constant. In these models the inflationary stage of the Universe evolution changes into a quasi-cyclic stage…

General Relativity and Quantum Cosmology · Physics 2014-02-26 I. Ya. Aref'eva , N. V. Bulatov , R. V. Gorbachev , S. Yu. Vernov

In the paper we investigate observational constraints on coupling to gravity constant parameter $\xi$ using distant supernovae SNIa data, baryon oscillation peak (BOP), the cosmic microwave background radiation (CMBR) shift parameter, and…

Astrophysics · Physics 2009-06-23 Marek Szydlowski , Orest Hrycyna , Aleksandra Kurek
‹ Prev 1 2 3 10 Next ›