Download or read book Fundamental Aspects of Asymptotic Safety in Quantum Gravity written by Zoë H. Slade and published by Springer. This book was released on 2019-07-08 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: After an extensive introduction to the asymptotic safety approach to quantum gravity, this thesis explains recent key advances reported in four influential papers. Firstly, two exact solutions to the reconstruction problem (how to recover a bare action from the effective average action) are provided. Secondly, the fundamental requirement of background independence in quantum gravity is successfully implemented. Working within the derivative expansion of conformally reduced gravity, the notion of compatibility is developed, uncovering the underlying reasons for background dependence generically forbidding fixed points in such models. Thirdly, in order to understand the true nature of fixed-point solutions, one needs to study their asymptotic behaviour. The author carefully explains how to find the asymptotic form of fixed point solutions within the f(R) approximation. Finally, the key findings are summarised and useful extensions of the work are identified. The thesis finishes by considering the need to incorporate matter into the formalism in a compatible way and touches upon potential opportunities to test asymptotic safety in the future.
Download or read book Fundamental Aspects of Asymptotic Safety in Quantum Gravity written by Zoèe H. Slade and published by . This book was released on 2019 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: After an extensive introduction to the asymptotic safety approach to quantum gravity, this thesis explains recent key advances reported in four influential papers. Firstly, two exact solutions to the reconstruction problem (how to recover a bare action from the effective average action) are provided. Secondly, the fundamental requirement of background independence in quantum gravity is successfully implemented. Working within the derivative expansion of conformally reduced gravity, the notion of compatibility is developed, uncovering the underlying reasons for background dependence generically forbidding fixed points in such models. Thirdly, in order to understand the true nature of fixed-point solutions, one needs to study their asymptotic behaviour. The author carefully explains how to find the asymptotic form of fixed point solutions within the f(R) approximation. Finally, the key findings are summarised and useful extensions of the work are identified. The thesis finishes by considering the need to incorporate matter into the formalism in a compatible way and touches upon potential opportunities to test asymptotic safety in the future.
Download or read book Fundamental Aspects of Asymptotic Safety in Quantum Gravity written by Zoë Helen Slade and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamental Aspects of Asymptotic Safety in Quantum Gravity written by Zoe Helen Slade and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Asymptotically Safe Gravity written by Alessia Benedetta Platania and published by . This book was released on 2018 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book seeks to construct a consistent fundamental quantum theory of gravity, which is often considered one of the most challenging open problems in present-day physics. It approaches this challenge using modern functional renormalization group techniques, and attempts to realize the idea of "Asymptotic Safety" originally proposed by S. Weinberg. Quite remarkably, the book makes significant progress regarding both the fundamental aspects of the program and its phenomenological consequences. The conceptual developments pioneer the construction of a well-behaved functional renormalization group equation adapted to spacetimes with a preferred time-direction. It is demonstrated that the Asymptotic Safety mechanism persists in this setting and extends to many phenomenologically interesting gravity-matter systems. These achievements constitute groundbreaking steps towards bridging the gap between quantum gravity in Euclidean and Lorentzian spacetimes. The phenomenological applications cover core topics in quantum gravity, e.g. constructing a phenomenologically viable cosmological evolution based on quantum gravity effects in the very early universe, and analyzing quantum corrections to black holes forming from a spherical collapse. As a key feature, all developments are presented in a comprehensive and accessible way. This makes the work a timely and valuable guide into the rapidly evolving field of Asymptotic Safety.
Download or read book Asymptotic Safety and Black Holes written by Kevin Falls and published by Springer Science & Business Media. This book was released on 2013-11-26 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the open challenges in fundamental physics is to combine Einstein's theory of general relativity with the principles of quantum mechancis. In this thesis, the question is raised whether metric quantum gravity could be fundamental in the spirit of Steven Weinberg's seminal asymptotic safety conjecture, and if so, what are the consequences for the physics of small, possibly Planck-size black holes? To address the first question, new techniques are provided which allow, for the first time, a self-consistent study of high-order polynomial actions including up to 34 powers in the Ricci scalar. These novel insights are then exploited to explain quantum gravity effects in black holes, including their horizon and causal structure, conformal scaling, evaporation, and the thermodynamics of quantum space-time. Results indicate upper limits on black hole temperature, and the existence of small black holes based on asymptotic safety for gravity and thermodynamical arguments.
Download or read book Quantum Gravity and the Functional Renormalization Group written by Martin Reuter and published by Cambridge University Press. This book was released on 2019-01-03 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: A self-contained pedagogical introduction to asymptotic safety and the functional renormalization group in quantum gravity, for graduate students and researchers.
Download or read book An Introduction To Covariant Quantum Gravity And Asymptotic Safety written by Roberto Percacci and published by World Scientific. This book was released on 2017-02-17 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers recent developments in the covariant formulation of quantum gravity. Developed in the 1960s by Feynman and DeWitt, by the 1980s this approach seemed to lead nowhere due to perturbative non-renormalizability. The possibility of non-perturbative renormalizability or 'asymptotic safety', originally suggested by Weinberg but largely ignored for two decades, was revived towards the end of the century by technical progress in the field of the renormalization group. It is now a very active field of research, providing an alternative to other approaches to quantum gravity.Written by one of the early contributors to this subject, this book provides a gentle introduction to the relevant ideas and calculational techniques. Several explicit calculations gradually bring the reader close to the current frontier of research. The main difficulties and present lines of development are also outlined.
Download or read book Quantum Gravity and the Functional Renormalization Group written by Martin Reuter and published by Cambridge University Press. This book was released on 2019-01-03 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: A self-contained pedagogical introduction to asymptotic safety and the functional renormalization group in quantum gravity, for graduate students and researchers.
Download or read book Asymptotic Safety and Black Holes written by Ronald Howland and published by Createspace Independent Publishing Platform. This book was released on 2017-12-06 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, the question is raised whether metric quantum gravity could be fundamental in the spirit of Steven Weinberg's seminal asymptotic safety conjecture, and if so, what the consequences would be for the physics of small, possibly Planck-size black holes. To address the first question, new techniques are provided which allow, for the first time, a self-consistent study of high-order polynomial actions including up to 34 powers in the Ricci scalar. These novel insights are then exploited to explain quantum gravity effects in black holes, including their horizon and causal structure, conformal scaling, evaporation, and the thermodynamics of quantum space-time.
Download or read book Approaches to Quantum Gravity written by Daniele Oriti and published by Cambridge University Press. This book was released on 2009-03-05 with total page 605 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book General Relativity Black hole astrophysics written by W. Israel and published by . This book was released on 2010 with total page 1064 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conversations on Quantum Gravity written by Jácome Armas and published by Cambridge University Press. This book was released on 2021-08-26 with total page 719 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leading theorists share their important insights into the ongoing quest of theoretical physics to find a quantum theory of gravity.
Download or read book Quantum Gravity written by Rodrigo Sobreiro and published by IntechOpen. This book was released on 2012-02-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The unification between gravity and quantum field theory is one of the major problems in contemporary fundamental Physics. It exists for almost one century, but a final answer is yet to be found. Although string theory and loop quantum gravity have brought many answers to the quantum gravity problem, they also came with a large set of extra questions. In addition to these last two techniques, many other alternative theories have emerged along the decades. This book presents a series of selected chapters written by renowned authors. Each chapter treats gravity and its quantization through known and alternative techniques, aiming a deeper understanding on the quantum nature of gravity. Quantum Gravity is a book where the reader will find a fine collection of physical and mathematical concepts, an up to date research, about the challenging puzzle of quantum gravity.
Download or read book Quantum Gravity written by Steff Jaywan and published by Dedona Publishing. This book was released on with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum gravity is a field of theoretical physics that aims to describe the gravitational force according to the principles of quantum mechanics. Key Concepts General relativity, developed by Albert Einstein, describes gravity as the curvature of spacetime caused by mass and energy. It works extremely well at large scales, such as in predicting planetary orbits and the behavior of black holes. On the other hand, quantum mechanics deals with the fundamental behavior of particles at the smallest scales, such as atoms and subatomic particles. It incorporates principles like wave-particle duality, quantization, and uncertainty. The Need for Quantum Gravity Despite their success, general relativity and quantum mechanics are fundamentally incompatible. General relativity treats gravity as a smooth, continuous field, while quantum mechanics relies on quantized fields and inherently probabilistic events. When attempting to describe situations where both quantum effects and strong gravitational effects are significant, such as in the vicinity of black holes or during the Big Bang, the theories conflict. Quantum gravity aims to unify these two frameworks. Approaches to Quantum Gravity Several approaches have been proposed to formulate a theory of quantum gravity. String theory proposes that fundamental particles are not point-like but instead one-dimensional "strings" that vibrate at different frequencies. This theory inherently includes gravity and attempts to unify all fundamental forces. Loop quantum gravity (LQG) focuses on quantizing spacetime itself, positing that spacetime has a discrete structure at the smallest scales and attempts to describe the quantum properties of spacetime directly, without relying on a background. Causal dynamical triangulations (CDT) is a method of simulating quantum spacetime by breaking it down into discrete, simplicial building blocks, like triangles or tetrahedra, and studying how these blocks combine to form spacetime. Asymptotic safety aims to define a quantum theory of gravity that remains consistent and finite at all energy scales by identifying a fixed point in the theory's parameter space where the theory remains predictive and well-behaved.
Download or read book Quantum Gravity written by Claus Kiefer and published by Oxford University Press. This book was released on 2012-04-05 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum theory and Einstein's theory of relativity are at the centre of modern theoretical physics, yet, the consistent unification of both theories is still elusive. This book offers an up-to-date introduction into the attempts to construct a unified theory of "quantum gravity".
Download or read book Quantum Gravity written by Bertfried Fauser and published by Springer Science & Business Media. This book was released on 2007-02-15 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the reader with an overview of the different mathematical attempts to quantize gravity written by leading experts in this field. Also discussed are the possible experimental bounds on quantum gravity effects. The contributions have been strictly refereed and are written in an accessible style. The present volume emerged from the 2nd Blaubeuren Workshop "Mathematical and Physical Aspects of Quantum Gravity".
