Background Independence In Classical And Quantum Gravity

Author : James Read
Publisher : Oxford University Press
Page : 159 pages
File Size : 49,6 Mb
Release : 2023-11-09
Category : Philosophy
ISBN : 9780192889133

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Background Independence in Classical and Quantum Gravity by James Read Pdf

It is often claimed that Einstein's magnum opus—-his 1915 theory of General Relativity—-is distinguished from other theories of space and time in virtue of its background independence. It's also often claimed that background independence is an essential feature of any quantum theory of gravity. But are these claims true? This book aspires to offer definitive answers to both of these questions, by (a) charting the space of possible definitions of background independence, and (b) applying said definitions to various classical and quantum theories of gravity. The outcome, in brief, is as follows: General Relativity is not unique by virtue of its background independence (and, indeed, fails to be background independent on some popular definitions); moreover, the situation in the case of quantum theories of gravity is delicate, because (i) there are viable such theories which (by some accounts, at least) fail to be background independent, but also (ii) theories (e.g. perturbative string theory) which have often been dismissed for (allegedly) being background dependent in fact, on many accounts, are better classified as background independent. In giving these answers in rigorous detail, this book seeks to elevate the standards and generality of future discussions of background independence in the foundations of spacetime theories.

Author : Edward Anderson
Publisher : Springer
Page : 920 pages
File Size : 46,5 Mb
Release : 2017-09-18
Category : Science
ISBN : 9783319588483

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The Problem of Time by Edward Anderson Pdf

This book is a treatise on time and on background independence in physics. It first considers how time is conceived of in each accepted paradigm of physics: Newtonian, special relativity, quantum mechanics (QM) and general relativity (GR). Substantial differences are moreover uncovered between what is meant by time in QM and in GR. These differences jointly source the Problem of Time: Nine interlinked facets which arise upon attempting concurrent treatment of the QM and GR paradigms, as is required in particular for a background independent theory of quantum gravity. A sizeable proportion of current quantum gravity programs - e.g. geometrodynamical and loop quantum gravity approaches to quantum GR, quantum cosmology, supergravity and M-theory - are background independent in this sense. This book's foundational topic is thus furthermore of practical relevance in the ongoing development of quantum gravity programs. This book shows moreover that eight of the nine facets of the Problem of Time already occur upon entertaining background independence in classical (rather than quantum) physics. By this development, and interpreting shape theory as modelling background independence, this book further establishes background independence as a field of study. Background independent mechanics, as well as minisuperspace (spatially homogeneous) models of GR and perturbations thereabout are used to illustrate these points. As hitherto formulated, the different facets of the Problem of Time greatly interfere with each others' attempted resolutions. This book explains how, none the less, a local resolution of the Problem of Time can be arrived at after various reconceptualizations of the facets and reformulations of their mathematical implementation. Self-contained appendices on mathematical methods for basic and foundational quantum gravity are included. Finally, this book outlines how supergravity is refreshingly different from GR as a realization of background independence, and what background independence entails at the topological level and beyond.

Author : James Read
Publisher : Oxford University Press
Page : 159 pages
File Size : 43,6 Mb
Release : 2024-02-09
Category : Philosophy
ISBN : 9780192889119

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Background Independence in Classical and Quantum Gravity by James Read Pdf

It is often claimed that Einstein's magnum opus---his 1915 theory of General Relativity---is distinguished from other theories of space and time in virtue of its background independence. It's also often claimed that background independence is an essential feature of any quantum theory of gravity. But are these claims true? This book aspires to offer definitive answers to both of these questions, by (a) charting the space of possible definitions of background independence, and (b) applying said definitions to various classical and quantum theories of gravity. The outcome, in brief, is as follows: General Relativity is not unique by virtue of its background independence (and, indeed, fails to be background independent on some popular definitions); moreover, the situation in the case of quantum theories of gravity is delicate, because (i) there are viable such theories which (by some accounts, at least) fail to be background independent, but also (ii) theories (e.g. perturbative string theory) which have often been dismissed for (allegedly) being background dependent in fact, on many accounts, are better classified as background independent. In giving these answers in rigorous detail, this book seeks to elevate the standards and generality of future discussions of background independence in the foundations of spacetime theories.

Author : Carlo Rovelli
Publisher : Cambridge University Press
Page : 516 pages
File Size : 53,8 Mb
Release : 2007-11-29
Category : Science
ISBN : 9781139456159

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Quantum Gravity by Carlo Rovelli Pdf

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.

Author : Dean Rickles,Steven French,Juha T. Saatsi
Publisher : Clarendon Press
Page : 288 pages
File Size : 55,8 Mb
Release : 2006-11-16
Category : Science
ISBN : 9780191515026

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The Structural Foundations of Quantum Gravity by Dean Rickles,Steven French,Juha T. Saatsi Pdf

Quantum gravity is the name given to a theory that unites general relativity - Einstein's theory of gravitation and spacetime - with quantum field theory, our framework for describing non-gravitational forces. The Structural Foundations of Quantum Gravity brings together philosophers and physicists to discuss a range of conceptual issues that surface in the effort to unite these theories, focusing in particular on the ontological nature of the spacetime that results. Although there has been a great deal written about quantum gravity from the perspective of physicists and mathematicians, very little attention has been paid to the philosophical aspects. This volume closes that gap, with essays written by some of the leading researchers in the field. Individual papers defend or attack a structuralist perspective on the fundamental ontologies of our physical theories, which offers the possibility of shedding new light on a number of foundational problems. It is a book that will be of interest not only to physicists and philosophers of physics but to anyone concerned with foundational issues and curious to explore new directions in our understanding of spacetime and quantum physics.

Author : Daniele Oriti
Publisher : Cambridge University Press
Page : 605 pages
File Size : 54,8 Mb
Release : 2009-03-05
Category : Science
ISBN : 9780521860451

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Approaches to Quantum Gravity by Daniele Oriti Pdf

Containing contributions from leading researchers in this field, this book provides a complete overview of this field from the frontiers of theoretical physics research for graduate students and researchers. It introduces the most current approaches to this problem, and reviews their main achievements.

Author : Karen Crowther
Publisher : Springer
Page : 205 pages
File Size : 48,5 Mb
Release : 2016-07-07
Category : Science
ISBN : 9783319395081

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Effective Spacetime by Karen Crowther Pdf

This book discusses the notion that quantum gravity may represent the "breakdown" of spacetime at extremely high energy scales. If spacetime does not exist at the fundamental level, then it has to be considered "emergent", in other words an effective structure, valid at low energy scales. The author develops a conception of emergence appropriate to effective theories in physics, and shows how it applies (or could apply) in various approaches to quantum gravity, including condensed matter approaches, discrete approaches, and loop quantum gravity.

Author : Domenico J. W. Giulini,Claus Kiefer,Claus Lämmerzahl
Publisher : Springer Science & Business Media
Page : 426 pages
File Size : 49,9 Mb
Release : 2003-09-16
Category : Science
ISBN : 354040810X

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Quantum Gravity by Domenico J. W. Giulini,Claus Kiefer,Claus Lämmerzahl Pdf

The relation between quantum theory and the theory of gravitation remains one of the most outstanding unresolved issues of modern physics. According to general expectation, general relativity as well as quantum (field) theory in a fixed background spacetime cannot be fundamentally correct. Hence there should exist a broader theory comprising both in appropriate limits, i.e., quantum gravity. This book gives readers a comprehensive introduction accessible to interested non-experts to the main issues surrounding the search for quantum gravity. These issues relate to fundamental questions concerning the various formalisms of quantization; specific questions concerning concrete processes, like gravitational collapse or black-hole evaporation; and the all important question concerning the possibility of experimental tests of quantum-gravity effects.

Author : Vincent R. Frignanni
Publisher : Unknown
Page : 0 pages
File Size : 41,5 Mb
Release : 2012
Category : Quantum gravity
ISBN : 161122957X

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Classical and Quantum Gravity by Vincent R. Frignanni Pdf

Classical and quantum gravity covers all aspects of gravitational physics and the theory of spacetime. This new book presents topical research in the study of classical and quantum gravity, including the weak field limit of fourth order gravity; the problem of time in quantum gravity; quantum correction and entropy spectrum in different gravity; quantum instability for charged particles on charged Nariai Black Holes and the equivalence of the generalised tetra formalism with the theory of general relativity.

Author : Astrid Eichhorn,Benjamin Bahr,Antonio D. Pereira
Publisher : Frontiers Media SA
Page : 298 pages
File Size : 41,7 Mb
Release : 2021-07-15
Category : Science
ISBN : 9782889710492

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Coarse Graining in Quantum Gravity: Bridging the Gap between Microscopic Models and Spacetime-Physics by Astrid Eichhorn,Benjamin Bahr,Antonio D. Pereira Pdf

Author : Dean Rickles,Steven French,Juha T. Saatsi
Publisher : Oxford University Press
Page : 283 pages
File Size : 41,5 Mb
Release : 2006-11-16
Category : Mathematics
ISBN : 9780199269693

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The Structural Foundations of Quantum Gravity by Dean Rickles,Steven French,Juha T. Saatsi Pdf

What is spacetime? General relativity and quantum field theory answer this question in different ways. This collection of essays looks at the problem of uniting these two fundamental theories of our world, focusing on the nature of space and time within this quantum framework.

Author : Thomas Thiemann
Publisher : Cambridge University Press
Page : 739 pages
File Size : 43,7 Mb
Release : 2008-11-13
Category : Science
ISBN : 9781139467599

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Modern Canonical Quantum General Relativity by Thomas Thiemann Pdf

This book provides a complete treatise of the canonical quantisation of general relativity and the loop quantum gravity theory. Mathematical concepts are provided, so it can be read by graduate students with a basic knowledge of quantum field theory or general relativity.

Author : Lee Smolin
Publisher : Basic Books
Page : 230 pages
File Size : 47,6 Mb
Release : 2008-03-18
Category : Science
ISBN : 9780465013241

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Three Roads To Quantum Gravity by Lee Smolin Pdf

"It would be hard to imagine a better guide to this difficult subject." -- Scientific American In Three Roads to Quantum Gravity, Lee Smolin provides an accessible overview of the attempts to build a final "theory of everything." He explains in simple terms what scientists are talking about when they say the world is made from exotic entities such as loops, strings, and black holes and tells the fascinating stories behind these discoveries: the rivalries, epiphanies, and intrigues he witnessed firsthand. "Provocative, original, and unsettling." -- The New York Review of Books "An excellent writer, a creative thinker." -- Nature

Author : Tiziana Vistarini
Publisher : Routledge
Page : 224 pages
File Size : 46,6 Mb
Release : 2019-06-12
Category : Philosophy
ISBN : 9781134842407

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The Emergence of Spacetime in String Theory by Tiziana Vistarini Pdf

The nature of space and time is one of the most fascinating and fundamental philosophical issues which presently engages at the deepest level with physics. During the last thirty years this notion has been object of an intense critical review in the light of new scientific theories which try to combine the principles of both general relativity and quantum theory—called theories of quantum gravity. This book considers the way string theory shapes its own account of spacetime disappearance from the fundamental level.

Author : Dean Rickles
Publisher : Elsevier
Page : 243 pages
File Size : 43,8 Mb
Release : 2008
Category : Science
ISBN : 9780444531162

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Symmetry, Structure, and Spacetime by Dean Rickles Pdf

In this book Rickles considers several interpretative difficulties raised by gauge-type symmetries (those that correspond to no change in physical state). The ubiquity of such symmetries in modern physics renders them an urgent topic in philosophy of physics. Rickles focuses on spacetime physics, and in particular classical and quantum general relativity. Here the problems posed are at their most pathological, involving the apparent disappearance of spacetime! Rickles argues that both traditional ontological positions should be replaced by a structuralist account according to which relational structure is what the physics is about. · Unified treatment of gauge symmetries and their relationship to ontology in physics · Brings philosophy of space and time into step with developments in modern physics · Argues against the received view on the implications of symmetries in physics · Provides elementary treatments of technical issues · Illustrates a novel defense of structuralism