English
Related papers

Related papers: Cosmic Inflation, Dark Energy and Gravitational Wa…

200 papers

A scenario of the inflaton evolution from cosmic inflation and matter creation to dark matter/dark energy today is presented. To start with, a model of the inflationary phase of the inflaton is introduced. The inflaton rolls down a hilltop…

High Energy Physics - Phenomenology · Physics 2023-04-07 B. S. Balakrishna

In this paper, we investigate D-term inflation within the framework of supergravity, employing the minimal K\"{a}hler potential. Following previous studies that revealed that this model can overcome the $\eta$-problem found in F-term…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-02 K. El Bourakadi , G. Otalora , A. Burton-Villalobos , H. Chakir , M. Ferricha-Alami , M. Bennai

We explore the role of dissipative effects during warm inflation leading to the small-scale enhancement of the power spectrum of curvature perturbations. In this paper, we specifically focus on non-canonical warm inflationary scenarios and…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-22 Richa Arya , Rajeev Kumar Jain , Arvind Kumar Mishra

The current accelerated universe could be produced by modified gravitational dynamics as it can be seen in particular in its Palatini formulation. We analyze here a specific non-linear gravity-scalar system in the first order Palatini…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Gianluca Allemandi , Andrzej Borowiec , Mauro Francaviglia , Sergei D. Odintsov

We study the production, spectrum and detectability of gravitational waves in models of the early Universe where first order phase transitions occur during inflation. We consider all relevant sources. The self-consistency of the scenario…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-16 Diego Chialva

Cosmological inflation provides the simplest and most promising mechanism for generating fluctuations for structure formation. Using powerful Hamilton-Jacobi methods, I will describe (1) how to compute density fluctuations and cosmic…

Astrophysics · Physics 2009-09-25 D. S. Salopek

Cosmological inflation remains to be a unique mechanism of generation of plausible initial conditions in the early universe. In particular, it generates the primordial quasiclassical perturbations with power spectrum determined by the…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-23 Yuri Shtanov

Cosmological phase transitions are thought to have taken place at the early Universe imprinting their properties on the observable Universe. There is strong evidence that, through the dynamics of a scalar field that lead a second order…

General Relativity and Quantum Cosmology · Physics 2021-12-08 Orfeu Bertolami

Does inflation provide a compelling explanation for why the universe is so large, so flat, and so old, and a predictive theory of density perturbations? In this brief contribution (based on the role of the author as moderator of the…

Astrophysics · Physics 2007-05-23 Robert H. Brandenberger

The theory of cosmological perturbations has become a cornerstone of modern quantitative cosmology since it is the framework which provides the link between the models of the very early Universe such as the inflationary Universe scenario…

High Energy Physics - Theory · Physics 2017-08-23 Robert H. Brandenberger

In bounce inflation scenario, the inflation is singularity-free, while the advantages of inflation are reserved. We analytically calculate the power spectrum of its primordial gravitational waves (GWs), and show a universal result including…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Hai-Guang Li , Yong Cai , Yun-Song Piao

In effective supergravity theories following from the superstring, a modulus field can quite naturally set the neccessary initial conditions for successful cosmological inflation to be driven by a hidden sector scalar field. The leading…

High Energy Physics - Phenomenology · Physics 2007-05-23 Subir Sarkar

The primordial gravitational waves (\textbf{PGW}) have been generated by inflationary amplification of the primordial (quantum) fluctuations. It is true that they have not been recorded directly so far, but their spectrum can help a lot in…

General Relativity and Quantum Cosmology · Physics 2022-02-23 Taimur Mohammadi , Behrooz Malekolkalami , Khabat Ghamari

Supersolid inflation is a class of inflationary theories that simultaneously breaks time and space reparameterization invariance during inflation, with distinctive features for the dynamics of cosmological fluctuations. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Angelo Ricciardone , Gianmassimo Tasinato

Scalar-tensor theories of gravity that embrace conformal coupling to the scalar curvature are the focal point of cosmology on discussions of inflation and late-time accelerating universe. Although there exists a stringent nucleo-synthesis…

General Relativity and Quantum Cosmology · Physics 2022-04-26 M. Yoshimura

We calculate the full spectrum, as observed today, of the cosmological gravitational waves generated within a model based on loop quantum cosmology. It is assumed that the universe, after the transition to the classical regime, undergoes a…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Paulo M. Sá , Alfredo B. Henriques

At its very beginning, the universe is believed to have grown exponentially in size via the mechanism of inflation. The almost scale-invariant density perturbation spectrum predicted by inflation is strongly supported by cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 David F. Chernoff , S. -H. Henry Tye

A unified description of inflation, dark energy, and dark matter is presented within a two-scalar-field cosmological model. Inflation, assumed to be of the warm type, is driven by one of the scalar fields, which, shortly after the end of…

General Relativity and Quantum Cosmology · Physics 2020-11-24 Paulo M. Sá

Scalar induced gravitational waves contribute to the cosmological gravitational wave background. They can be related to the primordial density power spectrum produced towards the end of inflation and therefore are a convenient new tool to…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-10 Raphael Picard , Karim A. Malik

Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of…

‹ Prev 1 8 9 10 Next ›