Quantum Cosmology

Quantum Cosmology PDF Author: Martin Bojowald
Publisher: Springer Science & Business Media
ISBN: 1441982752
Category : Science
Languages : en
Pages : 306

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Book Description
Consequences of quantum gravity on grander scales are expected to be enormous: only such a theory can show how black holes really behave and where our universe came from. Applications of loop quantum gravity to cosmology have especially by now shed much light on cosmic evolution of a universe in a fundamental, microscopic description. Modern techniques are explained in this book which demonstrate how the universe could have come from a non-singular phase before the big bang, how equations for the evolution of structure can be derived, but also what fundamental limitations remain to our knowledge of the universe before the big bang. The following topics will be covered in this book: Hamiltonian cosmology: a general basic treatment of isotropy, perturbations and their role for observations; useful in general cosmology. Effective equations: an efficient way to evaluate equations of quantum gravity, which is also useful in other areas of physics where quantum theory is involved. Loop quantization: a new formalism for the atomic picture of space-time; usually presented at a sophisticated mathematical level, but evaluated here from an intuitive physical side. The book will start with physical motivations, rather than mathematical developments which is more common in other expositions of this field. All the required mathematical methods will be presented, but will not distract the reader from seeing the underlying physics. Simple but representative models will be presented first to show the basic features, which are then used to work upwards to a general description of quantum gravity and its applications in cosmology. This will make the book accessible to a more general physics readership.

Quantum Cosmology

Quantum Cosmology PDF Author: Martin Bojowald
Publisher: Springer Science & Business Media
ISBN: 1441982752
Category : Science
Languages : en
Pages : 306

Get Book Here

Book Description
Consequences of quantum gravity on grander scales are expected to be enormous: only such a theory can show how black holes really behave and where our universe came from. Applications of loop quantum gravity to cosmology have especially by now shed much light on cosmic evolution of a universe in a fundamental, microscopic description. Modern techniques are explained in this book which demonstrate how the universe could have come from a non-singular phase before the big bang, how equations for the evolution of structure can be derived, but also what fundamental limitations remain to our knowledge of the universe before the big bang. The following topics will be covered in this book: Hamiltonian cosmology: a general basic treatment of isotropy, perturbations and their role for observations; useful in general cosmology. Effective equations: an efficient way to evaluate equations of quantum gravity, which is also useful in other areas of physics where quantum theory is involved. Loop quantization: a new formalism for the atomic picture of space-time; usually presented at a sophisticated mathematical level, but evaluated here from an intuitive physical side. The book will start with physical motivations, rather than mathematical developments which is more common in other expositions of this field. All the required mathematical methods will be presented, but will not distract the reader from seeing the underlying physics. Simple but representative models will be presented first to show the basic features, which are then used to work upwards to a general description of quantum gravity and its applications in cosmology. This will make the book accessible to a more general physics readership.

100 Years of Relativity

100 Years of Relativity PDF Author: Abhay Ashtekar
Publisher: World Scientific
ISBN: 9812700986
Category : Science
Languages : en
Pages : 527

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Book Description
Thanks to Einstein''s relativity theories, our notions of space and time underwent profound revisions about a 100 years ago. The resulting interplay between geometry and physics has dominated all of fundamental physics since then. This volume contains contributions from leading researchers, worldwide, who have thought deeply about the nature and consequences of this interplay. The articles take a long-range view of the subject and distill the most important advances in broad terms, making them easily accessible to non-specialists. The first part is devoted to a summary of how relativity theories were born (J Stachel). The second part discusses the most dramatic ramifications of general relativity, such as black holes (P Chrusciel and R Price), space-time singularities (H Nicolai and A Rendall), gravitational waves (P Laguna and P Saulson), the large scale structure of the cosmos (T Padmanabhan); experimental status of this theory (C Will) as well as its practical application to the GPS system (N Ashby). The last part looks beyond Einstein and provides glimpses into what is in store for us in the 21st century. Contributions here include summaries of radical changes in the notions of space and time that are emerging from quantum field theory in curved space-times (Ford), string theory (T Banks), loop quantum gravity (A Ashtekar), quantum cosmology (M Bojowald), discrete approaches (Dowker, Gambini and Pullin) and twistor theory (R Penrose).

Loop Quantum Gravity

Loop Quantum Gravity PDF Author: Abhay Ashtekar
Publisher: World Scientific Publishing Company
ISBN: 9789813209923
Category : Quantum cosmology
Languages : en
Pages : 0

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Book Description
"Over the last decade, several important advances have occurred, that include the continuum and classical limit of the non-perturbative theory on the conceptual side, and concrete ideas on confronting quantum gravity with observations in cosmology. This volume takes the reader from basics to recent advances, thereby bridging an important gap. It presents a snapshot of the state-of-the-art in loop quantum gravity from the perspective of young leading researchers. The goal is two-fold: to provide a contemporary introduction to the entire field for students and post-docs and, an overview of the current status for more senior researchers. These overviews present the latest developments that are not discussed in existing books, particularly the applications to the cosmology of the early universe and quantum aspects of black holes"--

A First Course in Loop Quantum Gravity

A First Course in Loop Quantum Gravity PDF Author: Rodolfo Gambini
Publisher: OUP Oxford
ISBN: 0191003239
Category : Science
Languages : en
Pages : 192

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Book Description
This book provides an accessible introduction to loop quantum gravity and some of its applications, at a level suitable for undergraduate students and others with only a minimal knowledge of college level physics. In particular it is not assumed that the reader is familiar with general relativity and only minimally familiar with quantum mechanics and Hamiltonian mechanics. Most chapters end with problems that elaborate on the text, and aid learning. Applications such as loop quantum cosmology, black hole entropy and spin foams are briefly covered. The text is ideally suited for an undergraduate course in the senior year of a physics major. It can also be used to introduce undergraduates to general relativity and quantum field theory as part of a 'special topics' type of course.

Quantum Gravity

Quantum Gravity PDF Author: Carlo Rovelli
Publisher: Cambridge University Press
ISBN: 1139456156
Category : Science
Languages : en
Pages : 516

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Book Description
Quantum gravity is perhaps the most important open problem in fundamental physics. It is the problem of merging quantum mechanics and general relativity, the two great conceptual revolutions in the physics of the twentieth century. The loop and spinfoam approach, presented in this 2004 book, is one of the leading research programs in the field. The first part of the book discusses the reformulation of the basis of classical and quantum Hamiltonian physics required by general relativity. The second part covers the basic technical research directions. Appendices include a detailed history of the subject of quantum gravity, hard-to-find mathematical material, and a discussion of some philosophical issues raised by the subject. This fascinating text is ideal for graduate students entering the field, as well as researchers already working in quantum gravity. It will also appeal to philosophers and other scholars interested in the nature of space and time.

Loop Quantum Gravity For Everyone

Loop Quantum Gravity For Everyone PDF Author: Rodolfo Gambini
Publisher: World Scientific
ISBN: 9811211973
Category : Science
Languages : en
Pages : 103

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Book Description
'In this remarkably well-written text, the authors introduce readers gently to the conceptual bricks of LQG without using any mathematics (quite an achievement). The debate started with the discovery that the space-time geometry of general relativity can be written in terms of the electromagnetic field. This led to intersecting graphs called loops. Now known as spin networks, they are the foundations of LQG. This slender volume discusses applications of LQG to black holes and cosmology and introduces the notion of spin foam, acknowledging that as yet the theory, though elegant, has no experimental confirmation … This book offers a fascinating introduction to an esoteric realm otherwise accessible to only a fortunate few.Summing Up: Highly recommended. Upper-division undergraduates. Graduate students and faculty researchers.'CHOICEChoice Outstanding Academic Title for 2020Loop quantum gravity is one of the main contenders to unify Einstein's general theory of relativity and quantum mechanics, therefore providing a quantum theory of gravity. If these words do not mean much to you, do not worry, we will define them in simple terms.This book describes loop quantum gravity and its applications to cosmology, black holes and spin foams without using formulas. It is concise and has a light style that makes for easy reading yet covering many of the cutting-edge developments in the field. It also addresses some of the controversies that surround these topics as they are incomplete science.

Covariant Loop Quantum Gravity

Covariant Loop Quantum Gravity PDF Author: Carlo Rovelli
Publisher: Cambridge University Press
ISBN: 1107069629
Category : Science
Languages : en
Pages : 267

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Book Description
A comprehensible introduction to the most fascinating research in theoretical physics: advanced quantum gravity. Ideal for researchers and graduate students.

Quantum Gravity and Quantum Cosmology

Quantum Gravity and Quantum Cosmology PDF Author: Gianluca Calcagni
Publisher: Springer
ISBN: 3642330363
Category : Science
Languages : en
Pages : 402

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Book Description
Quantum gravity has developed into a fast-growing subject in physics and it is expected that probing the high-energy and high-curvature regimes of gravitating systems will shed some light on how to eventually achieve an ultraviolet complete quantum theory of gravity. Such a theory would provide the much needed information about fundamental problems of classical gravity, such as the initial big-bang singularity, the cosmological constant problem, Planck scale physics and the early-time inflationary evolution of our Universe. While in the first part of this book concepts of quantum gravity are introduced and approached from different angles, the second part discusses these theories in connection with cosmological models and observations, thereby exploring which types of signatures of modern and mathematically rigorous frameworks can be detected by experiments. The third and final part briefly reviews the observational status of dark matter and dark energy, and introduces alternative cosmological models. 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.

Classical and Quantum Cosmology

Classical and Quantum Cosmology PDF Author: Gianluca Calcagni
Publisher: Springer
ISBN: 3319411276
Category : Science
Languages : en
Pages : 854

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Book Description
This comprehensive textbook is devoted to classical and quantum cosmology, with particular emphasis on modern approaches to quantum gravity and string theory and on their observational imprint. It covers major challenges in theoretical physics such as the big bang and the cosmological constant problem. An extensive review of standard cosmology, the cosmic microwave background, inflation and dark energy sets the scene for the phenomenological application of all the main quantum-gravity and string-theory models of cosmology. Born of the author's teaching experience and commitment to bridging the gap between cosmologists and theoreticians working beyond the established laws of particle physics and general relativity, this is a unique text where quantum-gravity approaches and string theory are treated on an equal footing. As well as introducing cosmology to undergraduate and graduate students with its pedagogical presentation and the help of 45 solved exercises, this book, which includes an ambitious bibliography of about 3500 items, will serve as a valuable reference for lecturers and researchers.

Once Before Time

Once Before Time PDF Author: Martin Bojowald
Publisher: Knopf
ISBN: 0307272850
Category : Science
Languages : en
Pages : 309

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Book Description
Traces how the physics professor author used a new theory of loop quantum gravity to create a simple model of the universe that launched loop quantum cosmology, in a report that presents a step-by-step argument about the origins of the universe.