Modified Gravity and Cosmology - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Modified Gravity and Cosmology write by Emmanuel N. Saridakis. This book was released on 2021-12-10. Modified Gravity and Cosmology available in PDF, EPUB and Kindle. With a focus on modified gravity this book presents a review of the recent developments in the fields of gravity and cosmology, presenting the state of the art, high-lighting the open problems, and outlining the directions of future research. General Relativity and the ΛCDM framework are currently the standard lore and constitute the concordance paradigm of cosmology. Nevertheless, long-standing open theoretical issues, as well as possible new observational ones arising from the explosive development of cosmology in the last two decades, offer the motivation and lead a large amount of research to be devoted in constructing various extensions and modifications. In this review all extended theories and scenarios are first examined under the light of theoretical consistency, and are then applied in various geometrical backgrounds, such as the cosmological and the spherical symmetric ones. Their predictions at both the background and perturbation levels, and concerning cosmology at early, intermediate and late times, are then confronted with the huge amount of observational data that astrophysics and cosmology has been able to offer in the last two decades. Theories, scenarios and models that successfully and efficiently pass the above steps are classified as viable and are candidates for the description of Nature, allowing readers to get a clear overview of the state of the art and where the field of modified gravity is likely to go. This work was performed in the framework of the COST European Action “Cosmology and Astrophysics Network for Theoretical Advances and Training Actions” - CANTATA.
Introduction to Modified Gravity
Introduction to Modified Gravity - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Introduction to Modified Gravity write by Albert Petrov. This book was released on 2020-07-27. Introduction to Modified Gravity available in PDF, EPUB and Kindle. This book reviews various modified gravity models, including those with modifications in the pure gravitational sector; those involving extra fields, that is, scalar-tensor and vector-tensor gravity theories; gravity models with Lorentz symmetry breaking; and nonlocal gravity models. The authors discuss both classical and quantum aspects of these theories. The book is unique in bringing together all the current alternatives to Einstein gravity in one source and serves as an excellent starting point for graduate students and other newcomers seeking an overview.
Introduction to Modified Gravity
Introduction to Modified Gravity - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Introduction to Modified Gravity write by Albert Petrov. This book was released on 2023-11-16. Introduction to Modified Gravity available in PDF, EPUB and Kindle. This book reviews various modified gravity models, including those with modifications in the pure gravitational sector; those involving extra fields, that is, scalar-tensor and vector-tensor gravity theories; gravity models with Lorentz symmetry breaking; and nonlocal gravity models. The authors discuss both classical and quantum aspects of these theories. The book is unique in bringing together all the current alternatives to Einstein gravity in one source and serves as an excellent starting point for graduate students and other newcomers seeking an overview. This second edition has been expanded with new results from a variety of approaches including f(R,Q,P) gravity, galileon gravity and massive gravity. Extended discussions of Lorentz-breaking terms and of non-local field theory have been added and a completely new chapter is devoted to models based on non-Riemannian geometry.
Generalized Perturbations in Modified Gravity and Dark Energy
Generalized Perturbations in Modified Gravity and Dark Energy - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Generalized Perturbations in Modified Gravity and Dark Energy write by Jonathan Pearson. This book was released on 2013-09-20. Generalized Perturbations in Modified Gravity and Dark Energy available in PDF, EPUB and Kindle. When predictions of Einstein's theory of General Relativity are compared against observations of our Universe, a huge inconsistency is found. The most popular fix for this inconsistency is to "invent" around 94% of the content of the universe: dark matter and dark energy. The dark energy is some exotic substance responsible for the apparent observed acceleration of the Universe. Another fix is to modify the theory of gravity: it is entirely plausible that Einstein's theory of General Relativity breaks down on cosmological scales, just as Newton's theory of gravity breaks down in the extreme gravitational field of the Sun. There are many alternative theories of gravity, each with the aim of describing observations of our Universe where General Relativity fails. Whether it is dark energy or some modified theory of gravity, it is clear that there is some "dark sector" in the Universe. In this thesis the author constructs a unifying framework for understanding the observational impact of general classes of dark sector theories, by formulating equations of state for the dark sector perturbations.
Modifications of Einstein's Theory of Gravity at Large Distances
Modifications of Einstein's Theory of Gravity at Large Distances - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Modifications of Einstein's Theory of Gravity at Large Distances write by Eleftherios Papantonopoulos. This book was released on 2014-11-04. Modifications of Einstein's Theory of Gravity at Large Distances available in PDF, EPUB and Kindle. In the last few years modified gravity theories have been proposed as extensions of Einstein's theory of gravity. Their main motivation is to explain the latest cosmological and astrophysical data on dark energy and dark matter. The study of general relativity at small scales has already produced important results (cf e.g. LNP 863 Quantum Gravity and Quantum Cosmology) while its study at large scales is challenging because recent and upcoming observational results will provide important information on the validity of these modified theories. In this volume, various aspects of modified gravity at large scales will be discussed: high-curvature gravity theories; general scalar-tensor theories; Galileon theories and their cosmological applications; F(R) gravity theories; massive, new massive and topologically massive gravity; Chern-Simons modifications of general relativity (including holographic variants) and higher-spin gravity theories, to name but a few of the most important recent developments. Edited and authored by leading researchers in the field and cast into the form of a multi-author textbook at postgraduate level, this volume will be of benefit to all postgraduate students and newcomers from neighboring disciplines wishing to find a comprehensive guide for their future research.
