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Related papers: Inflation and Precision Cosmology

200 papers

In constant-roll inflation, the scalar field that drives the accelerated expansion of the Universe is rolling down its potential at a constant rate. Within this framework, we highlight the relations between the Hubble slow-roll parameters…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-08 Alexandros Karam , Luca Marzola , Thomas Pappas , Antonio Racioppi , Kyriakos Tamvakis

In this talk I will review the present status of inflationary cosmology and its emergence as the basic paradigm behind the Standard Cosmological Model, with parameters determined today at better than 10% level from CMB and LSS observations.…

High Energy Physics - Phenomenology · Physics 2009-11-07 Juan Garcia-Bellido

We examine the dynamics of inflation driven by multiple, interacting scalar fields and derive a multi field version of the Hubble slow roll expansion. We show that the properties of this expansion naturally generalize those of the single…

Astrophysics · Physics 2013-05-29 Richard Easther , John T Giblin

We present uniform rate inflation in a modified $f(T, \mathcal{T}) $ gravity. It is found that early inflation can be realized even with a scalar field field with a quadratic potential and a negative cosmological constant. We construct…

General Relativity and Quantum Cosmology · Physics 2025-07-02 Priyanka Mandal , B. C. Paul

The evolution of a scalar field is explored taking into account the presence of a background fluid in a positively curved Universe in the framework of loop quantum cosmology. Though the mechanism that provides the initial conditions for…

Astrophysics · Physics 2009-11-13 N. J. Nunes

The calculation of scalar gravitational and matter perturbations during multiple-field inflation valid to first order in slow roll is discussed. These fields may be the coordinates of a non-trivial field manifold and hence have non-minimal…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. J. W. van Tent , S. Groot Nibbelink

A new method for predicting inflationary cosmological perturbations, based on the Wentzel-Kramers-Brillouin (WKB) approximation, is presented. A general expression for the WKB scalar and tensor power spectra is derived. The main advantage…

Astrophysics · Physics 2009-11-07 Jerome Martin , Dominik J. Schwarz

We study the WKB approximation beyond leading order for cosmological perturbations during inflation. To first order in the slow-roll parameters, we show that an improved WKB approximation leads to analytical results agreeing to within 0.1%…

General Relativity and Quantum Cosmology · Physics 2008-11-26 R. Casadio , F. Finelli , M. Luzzi , G. Venturi

We develop a frame-covariant formulation of inflation in the slow-roll approximation by generalizing the inflationary attractor solution for scalar-curvature theories. Our formulation gives rise to new generalized forms for the potential…

High Energy Physics - Phenomenology · Physics 2016-06-22 Daniel Burns , Sotirios Karamitsos , Apostolos Pilaftsis

We discuss the possibility that the inflationary paradigm, undoubtfully today's best framework to understand all the present cosmological data, may still have some viable challengers. The underlying idea for such discussions is that…

General Relativity and Quantum Cosmology · Physics 2010-11-15 P. Peter

Dynamical models of inflation are given with composite inflatons by means of massive supersymmetric gauge theory. Nearly flat directions and stable massive ones in the potential are identified and slow-roll during inflation is examined.…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Hamaguchi , K. -I. Izawa , H. Nakajima

Inflation is often described through the dynamics of a scalar field, slow-rolling in a suitable potential. Ultimately, this inflaton must be identified as the expectation value of a quantum field, evolving in a quantum effective potential.…

High Energy Physics - Phenomenology · Physics 2021-05-11 Jens O. Andersen , Magdalena Eriksson , Anders Tranberg

The slow-roll approximation is the usual starting point to study the constraints imposed on the inflaton potential parameters by the observational data. We show that, for a potential exhibiting at least two extrema and giving rise to a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Tiago Charters , Jose P. Mimoso , Ana Nunes

The first aim of this lecture is to highlight two areas of recent progress in inflationary cosmology, namely reheating and the quantum theory of cosmological perturbations. The second aim is to discuss important conceptual problems for the…

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

A short introduction to structure formation is given, followed by a discussion of the possible characteristics of the initial perturbations assuming a generic inflationary origin. Observational data related to large-scale structure and the…

Astrophysics · Physics 2014-10-13 Pedro Viana

Inflation is a bold and expansive extension of the Standard Cosmology. It holds the promise to extend our understanding of the Universe to within 10^{-32}sec of the big bang and answer most of the pressing questions in cosmology. Its…

Astrophysics · Physics 2007-05-23 Michael S. Turner

The big bang model and the history of the early universe according to the grand unified theories are introduced. The shortcomings of big bang are discussed together with their resolution by inflationary cosmology. Inflation, the subsequent…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Lazarides

We study the inflationary dynamics in Brane World gravity and look for observational signatures of any deviation from the standard General Relativity based results of Cosmological Perturbation Theory. We first review the standard paradigm…

General Relativity and Quantum Cosmology · Physics 2015-12-31 Argha Banerjee

We develop in this thesis the principles governing the production of our universe's primordial inhomogeneities during its early phase of inflation. As a guiding thread we ask what physics during inflation can lead to perturbations so large…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-18 Samuel Passaglia

A new inflationary scenario driven by a slowly-rolling homogeneous scalar field whose potential $V\left(\varphi\right)$ is given by a generalized exponential function is investigated. Within the {\it slow-roll} approximation we obtain the…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-17 B. W. Ribeiro , I. M. Macêdo , F. C. Carvalho