Delta N Formalism In Cosmological Perturbation Theory

Delta N Formalism In Cosmological Perturbation Theory PDF Author: Ali Akbar Abolhasani
Publisher: World Scientific
ISBN: 9813238771
Category : Science
Languages : en
Pages : 182

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Book Description
Early Universe cosmology is an active area of research and cosmic inflation is a pillar of modern cosmology. Among predictions of inflation, observationally the most important one is the generation of cosmological perturbations from quantum vacuum fluctuations that source all inhomogeneous structures in the Universe, not to mention the large-scale structures such as clusters of galaxies.Cosmological perturbation theory is the basic tool to study the perturbations generated from inflation. There are a few different approaches to primordial cosmological perturbations. In the conventional approach one perturbs the field equations and after quantizing the perturbations by the use of the corresponding action, one calculates the power spectrum of cosmological observables. This approach extends to higher order perturbations such as bispectrum etc., but the analysis becomes increasingly difficult.The delta N formalism, the topic of this book, is an alternative approach. The novelty of this approach is that, under the condition that the scale of interest is very large so that the spatial derivatives may be ignored in the dynamics, it can be applied to all orders in perturbation theory and has a rigorous foundation in general relativity. Thanks to the fact that one can evaluate perturbations with only the knowledge of background solutions, it is proved to be much easier than the conventional approach in evaluating higher order effects in many cases.

Delta N Formalism In Cosmological Perturbation Theory

Delta N Formalism In Cosmological Perturbation Theory PDF Author: Ali Akbar Abolhasani
Publisher: World Scientific
ISBN: 9813238771
Category : Science
Languages : en
Pages : 182

Get Book Here

Book Description
Early Universe cosmology is an active area of research and cosmic inflation is a pillar of modern cosmology. Among predictions of inflation, observationally the most important one is the generation of cosmological perturbations from quantum vacuum fluctuations that source all inhomogeneous structures in the Universe, not to mention the large-scale structures such as clusters of galaxies.Cosmological perturbation theory is the basic tool to study the perturbations generated from inflation. There are a few different approaches to primordial cosmological perturbations. In the conventional approach one perturbs the field equations and after quantizing the perturbations by the use of the corresponding action, one calculates the power spectrum of cosmological observables. This approach extends to higher order perturbations such as bispectrum etc., but the analysis becomes increasingly difficult.The delta N formalism, the topic of this book, is an alternative approach. The novelty of this approach is that, under the condition that the scale of interest is very large so that the spatial derivatives may be ignored in the dynamics, it can be applied to all orders in perturbation theory and has a rigorous foundation in general relativity. Thanks to the fact that one can evaluate perturbations with only the knowledge of background solutions, it is proved to be much easier than the conventional approach in evaluating higher order effects in many cases.

Introduction To The Theory Of The Early Universe: Hot Big Bang Theory (Second Edition)

Introduction To The Theory Of The Early Universe: Hot Big Bang Theory (Second Edition) PDF Author: Valery A Rubakov
Publisher: World Scientific
ISBN: 9813220058
Category : Science
Languages : en
Pages : 594

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Book Description
This book is written from the viewpoint that a deep connection exists between cosmology and particle physics. It presents the results and ideas on both the homogeneous and isotropic Universe at the hot stage of its evolution and in later stages. The main chapters describe in a systematic and pedagogical way established facts and concepts on the early and the present Universe. The comprehensive treatment, hence, serves as a modern introduction to this rapidly developing field of science. To help in reading the chapters without having to constantly consult other texts, essential materials from General Relativity and the theory of elementary particles are collected in the appendices. Various hypotheses dealing with unsolved problems of cosmology, and often alternative to each other, are discussed at a more advanced level. These concern dark matter, dark energy, matter-antimatter asymmetry, etc.Particle physics and cosmology underwent rapid development between the first and the second editions of this book. In the second edition, many chapters and sections have been revised, and numerical values of particle physics and cosmological parameters have been updated.

The Primordial Density Perturbation

The Primordial Density Perturbation PDF Author: David H. Lyth
Publisher: Cambridge University Press
ISBN: 1139643746
Category : Science
Languages : en
Pages : 516

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Book Description
The origin and evolution of the primordial perturbation is the key to understanding structure formation in the earliest stages of the Universe. It carries clues to the types of physical phenomena active in that extreme high-density environment. Through its evolution, generating first the observed cosmic microwave background anisotropies and later the distribution of galaxies and dark matter in the Universe, it probes the properties and dynamics of the present Universe. This graduate-level textbook gives a thorough account of theoretical cosmology and perturbations in the early Universe, describing their observational consequences and showing how to relate such observations to primordial physical processes, particularly cosmological inflation. With ambitious observational programmes complementing ever-increasing sophistication in theoretical modelling, cosmological studies will remain at the cutting edge of astrophysical studies for the foreseeable future.

Applications of Cosmological Perturbation Theory

Applications of Cosmological Perturbation Theory PDF Author: Adam J. Christopherson
Publisher:
ISBN:
Category : Cosmic magnetic fields
Languages : en
Pages : 260

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Book Description


Modern Cosmology

Modern Cosmology PDF Author: Scott Dodelson
Publisher: Academic Press
ISBN: 0122191412
Category : Science
Languages : en
Pages : 462

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Book Description
An advanced text for senior undergraduates, graduate students and physical scientists in fields outside cosmology. This is a self-contained book focusing on the linear theory of the evolution of density perturbations in the universe, and the anisotropiesin the cosmic microwave background.

The Vector Mode in the Second-order Cosmological Perturbation Theory

The Vector Mode in the Second-order Cosmological Perturbation Theory PDF Author: Shohei Saga
Publisher: Springer
ISBN: 9811080070
Category : Science
Languages : en
Pages : 143

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Book Description
This thesis sheds valuable new light on the second-order cosmological perturbation theory, extensively discussing it in the context of cosmic microwave background (CMB) fluctuations. It explores the observational consequences of the second-order vector mode, and addresses magnetic field generation and the weak lensing signatures, which are key phenomena of the vector mode. The author demonstrates that the second-order vector mode, which never appears at the linear-order level, naturally arises from the non-linear coupling of the first-order scalar modes. This leads to the remarkable statement that the vector-order mode clearly contributes to the generation of cosmological magnetic fields. Moreover, the weak lensing observations are shown to be accessible to the vector mode. On the basis of ongoing and forthcoming observations, the thesis concludes that the second-order vector mode is detectable.

Physical Foundations of Cosmology

Physical Foundations of Cosmology PDF Author: Viatcheslav Mukhanov
Publisher: Cambridge University Press
ISBN: 1139447114
Category : Science
Languages : en
Pages : 454

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Book Description
Inflationary cosmology has been developed over the last twenty years to remedy serious shortcomings in the standard hot big bang model of the universe. This textbook, first published in 2005, explains the basis of modern cosmology and shows where the theoretical results come from. The book is divided into two parts; the first deals with the homogeneous and isotropic model of the Universe, the second part discusses how inhomogeneities can explain its structure. Established material such as the inflation and quantum cosmological perturbation are presented in great detail, however the reader is brought to the frontiers of current cosmological research by the discussion of more speculative ideas. An ideal textbook for both advanced students of physics and astrophysics, all of the necessary background material is included in every chapter and no prior knowledge of general relativity and quantum field theory is assumed.

Gauge Invariant Cosmological Perturbation Theory

Gauge Invariant Cosmological Perturbation Theory PDF Author: Ruth Durrer
Publisher:
ISBN: 9782884491112
Category :
Languages : en
Pages : 131

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Book Description


The Physics of the Early Universe

The Physics of the Early Universe PDF Author: Eleftherios Papantonopoulos
Publisher: Springer Science & Business Media
ISBN: 9783540227120
Category : Science
Languages : en
Pages : 322

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Book Description
The Physics of the Early Universe is an edited and expanded version of the lectures given at a recent summer school of the same name. Its aim is to present an advanced multi-authored textbook that meets the needs of both postgraduate students and young researchers interested in, or already working on, problems in cosmology and general relativity, with emphasis on the early universe. A particularly strong feature of the present work is the constructive-critical approach to the present mainstream theories, the careful assessment of some alternative approaches, and the overall balance between theoretical and observational considerations. As such, this book will also benefit experienced scientists and nonspecialists from related areas of research.

The Early Universe and Observational Cosmology

The Early Universe and Observational Cosmology PDF Author: Nora Bretón
Publisher: Springer Science & Business Media
ISBN: 9783540218470
Category : Science
Languages : en
Pages : 492

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Book Description
Spectacular experimental advances in observational cosmology have helped raise cosmology to the status of a genuine science, and it is now possible to test many speculative theoretical issues and to obtain reliable values for the key parameters defining our observable universe. This book has emerged from selected lectures given at the Mexican School on Gravitation and Mathematical Physics by leaders in their field. Conceived as both a broad survey and as topical coverage of the latest developments, it will benefit graduate students and newcomers to this field and provide researchers in the field with a modern source of reference.