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This thesis piles up the results of five works in the field of cosmological inflation, inflationary cosmological perturbations, cosmic microwave background(CMB) and weak gravitational lensing of cosmic microwave background.

General Relativity and Quantum Cosmology · Physics 2015-06-03 Barun Kumar Pal

In this review article, we discuss the current status and future prospects of perturbation theory as a means of studying the equilibrium thermodynamic and near-equilibrium transport properties of deconfined QCD matter. We begin with a brief…

High Energy Physics - Phenomenology · Physics 2020-10-14 Jacopo Ghiglieri , Aleksi Kurkela , Michael Strickland , Aleksi Vuorinen

In these lectures I review the standard hot big-bang cosmology, emphasizing its successes, its shortcomings, and its major challenge---a detailed understanding of the formation of structure in the Universe. I then discuss the motivations…

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

This work discusses scalar-tensor theories of gravity, with a focus on the Brans-Dicke subclass, and one that also takes note of the latter's equivalence with $f(R)$ gravitation theories. A 1+3 covariant formalism is used in this case to…

General Relativity and Quantum Cosmology · Physics 2018-01-08 Joseph Ntahompagaze , Amare Abebe , Manasse R. Mbonye

We adopt a covariant formalism to derive exact evolution equations for nonlinear perturbations, in a universe dominated by two scalar fields. These scalar fields are characterized by non-canonical kinetic terms and an arbitrary field space…

High Energy Physics - Theory · Physics 2009-01-23 Sebastien Renaux-Petel , Gianmassimo Tasinato

Coupling dark energy and dark matter through an effective fluid description is a very common procedure in cosmology, however it always remains in comoving coordinates in the special FLRW space. We construct a consistent, general, and…

General Relativity and Quantum Cosmology · Physics 2014-09-17 Valerio Faraoni , James B. Dent , Emmanuel N. Saridakis

I review two different connections between particle theory and early-Universe cosmology: (1) Cosmic-microwave-background (CMB) tests of inflation and (2) particle dark matter. The inflationary predictions of a flat Universe and a nearly…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski

First a review of Teleparallel theory is done with special emphasis in the derivation of conservation equations within this theory and in particular of energy-momentum conservation. Given that we are allowed to speak about the existence of…

General Relativity and Quantum Cosmology · Physics 2014-02-18 Mariano Hermida de La Rica

In recent years there has been growing interest in verifying the horizon-scale homogeneity of the Universe that follows from applying the Copernican Principle to the observed isotropy. This program has been stimulated by the discovery that…

Astrophysics · Physics 2008-11-26 J. P. Zibin

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

The covariant generalizations of the background dark sector coupling suggested in G. Mangano, G. Miele and V. Pettorino, Mod. Phys. Lett. A 18, 831 (2003) are considered. The evolution of perturbations is studied with detailed attention to…

General Relativity and Quantum Cosmology · Physics 2011-04-22 N. A. Koshelev

We study linear cosmological perturbations in a previously introduced family of deformations of general relativity characterized by the absence of new degrees of freedom. The homogeneous and isotropic background in this class of theories is…

General Relativity and Quantum Cosmology · Physics 2010-06-08 Kirill Krasnov , Yuri Shtanov

These lecture notes provide an introduction to cosmic inflation. In particular I will review the basic concepts of inflation, generation of density perturbations, and reheating after inflation.

High Energy Physics - Phenomenology · Physics 2007-05-23 Shinji Tsujikawa

A long-standing problem in primordial cosmology is to understand the precise relation between the stochastic formalism and standard perturbation theory for light scalar fields in inflationary spacetimes. A complete correspondence between…

High Energy Physics - Theory · Physics 2026-02-10 Gonzalo A. Palma , Spyros Sypsas

These lectures have been given to particle physicists, mostly experimentalists and very briefly and at a pedestrian level review the problems of dark matter. The content of the lectures is the following: 1. Introduction. 2. Cosmological…

Astrophysics · Physics 2015-06-24 A. D. Dolgov

In recent years there has been a lot of interest in discussing frame dependences/independences of the cosmological perturbations under the conformal transformations. This problem has previously been investigated in terms of the covariant…

General Relativity and Quantum Cosmology · Physics 2018-03-14 Yunlong Zheng , Yicen Mou , Haomin Rao , Mingzhe Li

Black-hole perturbation theory is a useful tool to investigate issues in astrophysics, high-energy physics, and fundamental problems in gravity. It is often complementary to fully-fledged nonlinear evolutions and instrumental to interpret…

General Relativity and Quantum Cosmology · Physics 2013-09-10 Paolo Pani

This chapter provides a review of the frameworks developed for cosmological perturbation theory in loop quantum cosmology, and applications to various models of the early universe including inflation, ekpyrosis and the matter bounce, with…

General Relativity and Quantum Cosmology · Physics 2024-03-08 Ivan Agullo , Anzhong Wang , Edward Wilson-Ewing

We investigate the production of dark matter from curvature perturbations produced during inflation or in standard cosmology, for example during first order phase transitions. Perturbations break Weyl flatness of the…

High Energy Physics - Phenomenology · Physics 2024-09-06 Raghuveer Garani , Michele Redi , Andrea Tesi

Slow-roll inflation generically makes several predictions: a flat Universe, primordial adiabatic density perturbations, and a stochastic gravity-wave background. Each inflation model will further predict specific relations between the…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski