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Related papers: Dilaton cosmology and phenomenology

200 papers

We studied the dilaton cosmology based on Weyl-Scaled induced gravity. The potential of dilaton field is taken as exponential form. An analytical solution of Einstein equation is found. The dilaton can be a candidate for dark energy that…

High Energy Physics - Theory · Physics 2007-05-23 H. Q. Lu , Z. G. Huang , W. Fang , K. F. Zhang

We consider $f(R,T)$ modified theories of gravity in the context of string theory inspired dilaton gravity. We deal with a specific model that under certain conditions describes the late time Universe in accord with observational data in…

High Energy Physics - Theory · Physics 2024-03-11 F. A. Brito , C. H. A. B. Borges , J. A. V. Campos , F. G. Costa

The environment-dependent dilaton field is a well-motivated candidate for dark energy and naturally arises in the strong coupling limit of string theory. In this article, we present the very first experimental constraints on the parameters…

General Relativity and Quantum Cosmology · Physics 2024-02-23 Hauke Fischer , Christian Käding , René I. P. Sedmik , Hartmut Abele , Philippe Brax , Mario Pitschmann

Aspects of string cosmology for critical and non-critical strings are discussed emphasizing the necessity to account for the dilaton dynamics for a proper incorporation of ``large - small" duality. This drastically modifies the intuition…

High Energy Physics - Theory · Physics 2009-09-17 A. A. Tseytlin , C. Vafa

We reveal a novel aspect of scale-invariant actions that allow matter to couple with a dilaton field: $\,$The dynamics of the dilaton can induce variations in the Planck constant $\hbar$ and speed of light $c$. $\,$Our mechanism for…

General Relativity and Quantum Cosmology · Physics 2025-03-13 Hoang Ky Nguyen

We discuss the two-dimensional dilaton gravity with a scalar field as the source matter. The coupling between the gravity and the scalar, massless, field is presented in an unusual form. We work out two examples of these couplings, and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcelo Alves

The chameleonic behaviour of the String theory dilaton is suggested. Some of the possible consequences of the chameleonic string dilaton are analyzed in detail. In particular, (1) we suggest a new stringy solution to the cosmological…

High Energy Physics - Theory · Physics 2011-11-10 Andrea Zanzi

We discuss the expected amplitude of a cosmic background of massive, non-relativistic dilatons, and we report recent results about its possible detection. This paper is a contracted version of a talk given at the 15th SIGRAV Conference on…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Gasperini

We discuss the two-dimensional dilaton gravity with a scalar field as the source matter. The coupling between the gravity and the scalar, massless, field is presented in an unusual form. We work out two examples of these couplings and…

General Relativity and Quantum Cosmology · Physics 2009-10-31 M. Alves , V. B. Bezerra

It is pointed out that string-loop effects may generate matter couplings for the dilaton allowing this scalar partner of the tensorial graviton to stay massless while contributing to macroscopic gravity in a way naturally compatible with…

General Relativity and Quantum Cosmology · Physics 2009-10-22 T. Damour , A. M. Polyakov

We review a few off-the-beaten-track ideas in cosmology. They solve a variety of fundamental problems; also they are fun. We start with a description of non-singular dilaton cosmology. In these scenarios gravity is modified so that the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Robert H. Brandenberger , Joao Magueijo

Experimental discovery of the dilaton would provide strong evidence for string theory. A light dilaton could show up in current tests of the inverse square law for gravity at sub-millimeter distances. In the large extra dimension scenario,…

High Energy Physics - Phenomenology · Physics 2009-10-31 David B. Kaplan , Mark B. Wise

We recently proposed a chameleonic solution to the cosmological constant problem - Phys. Rev. D82 (2010) 044006. One of the results of that paper is a non-equivalence of different conformal frames at the quantum level. In this letter we…

High Energy Physics - Theory · Physics 2012-06-21 Andrea Zanzi

We study some aspects of classical & quantum cosmology in the context of two-dimensionsal dilaton gravity theories with matter being described by a perfect fluid. We derive the classical equations obeyed by the metric function & the dilaton…

General Relativity and Quantum Cosmology · Physics 2010-11-11 M. A. Ahmed

The flat matter dominated Universe that dominated cosmological model building for much of the past 20 years does not correspond to the Universe in which we live. This has profound implications both for our understanding of dark matter, and…

Astrophysics · Physics 2007-05-23 Lawrence M. Krauss

We consider the effect of string inhomogeneities on the time dependent background of Brane Gas Cosmology. We derive the equations governing the linear perturbations of the dilaton-gravity background in the presence of string matter sources.…

High Energy Physics - Theory · Physics 2010-02-03 Scott Watson , Robert Brandenberger

We start with a brief account of the latest analysis of the Oklo phenomenon providing the still most stringent constraint on time-variability of the fine- structure constant $\alpha$. Comparing this with the recent result from the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Yasunori Fujii

We discuss some aspects of string cosmology with an emphasis on the role played by the dilaton. A cosmological scenario based on the assumption that all spatial dimensions are periodic so that winding modes play an important role is…

High Energy Physics - Theory · Physics 2007-05-23 A. A. Tseytlin

We investigate the cosmological properties of Galileon models with positive kinetic terms. We include both conformal and disformal couplings to matter and focus on constraints on the theory that arise because of these couplings. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Philippe Brax , Clare Burrage , Anne-Christine Davis , Giulia Gubitosi

We recently proposed a simple dilaton-derived quintessence model in which the scalar field was non-minimally coupled to cold dark matter, but not to `visible' matter. Such couplings can be attributed to the dilaton in the low energy limit…

Astrophysics · Physics 2010-12-09 Rachel Bean