Finding libraries that hold this item You may have already requested this item. Please select Ok if you would like to proceed with this request anyway. WorldCat is the world's largest library catalog, helping you find library materials online. Don't have an account? Your Web browser is not enabled for JavaScript.
Quantum gravity
Some features of WorldCat will not be available. Create lists, bibliographies and reviews: Search WorldCat Find items in libraries near you.
Advanced Search Find a Library. Your list has reached the maximum number of items. Please create a new list with a new name; move some items to a new or existing list; or delete some items. Your request to send this item has been completed. Citations are based on reference standards. However, formatting rules can vary widely between applications and fields of interest or study.
The specific requirements or preferences of your reviewing publisher, classroom teacher, institution or organization should be applied. The E-mail Address es field is required. Please enter recipient e-mail address es. The E-mail Address es you entered is are not in a valid format. Please re-enter recipient e-mail address es.
You may send this item to up to five recipients. The name field is required.
Springer, Undergraduate Lecture Notes in Physics (ULNP) Books List | profhugodegaris
Please enter your name. The E-mail message field is required. Please enter the message.
Please verify that you are not a robot. They also face the common problem that, as yet, there is no way to put quantum gravity predictions to experimental tests, although there is hope for this to change as future data from cosmological observations and particle physics experiments becomes available. One suggested starting point is ordinary quantum field theories which are successful in describing the other three basic fundamental forces in the context of the standard model of elementary particle physics.
However, while this leads to an acceptable effective quantum field theory of gravity at low energies, [27] gravity turns out to be much more problematic at higher energies. For ordinary field theories such as quantum electrodynamics , a technique known as renormalization is an integral part of deriving predictions which take into account higher-energy contributions, [35] but gravity turns out to be nonrenormalizable: One attempt to overcome these limitations is to replace ordinary quantum field theory , which is based on the classical concept of a point particle , with a quantum theory of one-dimensional extended objects: In this way, string theory promises to be a unified description of all particles and interactions.
In what is called the second superstring revolution , it was conjectured that both string theory and a unification of general relativity and supersymmetry known as supergravity [40] form part of a hypothesized eleven-dimensional model known as M-theory , which would constitute a uniquely defined and consistent theory of quantum gravity. Sorting through this large family of solutions remains a major challenge. Loop quantum gravity seriously considers general relativity's insight that spacetime is a dynamical field and is therefore a quantum object.
Its second idea is that the quantum discreteness that determines the particle-like behavior of other field theories for instance, the photons of the electromagnetic field also affects the structure of space. The main result of loop quantum gravity is the derivation of a granular structure of space at the Planck length. This is derived from following considerations: In the case of electromagnetism, the quantum operator representing the energy of each frequency of the field has a discrete spectrum.
Thus the energy of each frequency is quantized, and the quanta are the photons. In the case of gravity, the operators representing the area and the volume of each surface or space region likewise have discrete spectrum. Thus area and volume of any portion of space are also quantized, where the quanta are elementary quanta of space. It follows, then, that spacetime has an elementary quantum granular structure at the Planck scale, which cuts off the ultraviolet infinities of quantum field theory.
The quantum state of spacetime is described in the theory by means of a mathematical structure called spin networks. Spin networks were initially introduced by Roger Penrose in abstract form, and later shown by Carlo Rovelli and Lee Smolin to derive naturally from a non-perturbative quantization of general relativity. Spin networks do not represent quantum states of a field in spacetime: The theory is based on the reformulation of general relativity known as Ashtekar variables , which represent geometric gravity using mathematical analogues of electric and magnetic fields.
The dynamics of the theory is today constructed in several versions. One version starts with the canonical quantization of general relativity. These represent histories of spin networks. There are a number of other approaches to quantum gravity. The approaches differ depending on which features of general relativity and quantum theory are accepted unchanged, and which features are modified.
As was emphasized above, quantum gravitational effects are extremely weak and therefore difficult to test. For this reason, the possibility of experimentally testing quantum gravity had not received much attention prior to the late s. However, in the past decade, physicists have realized that evidence for quantum gravitational effects can guide the development of the theory.
Since theoretical development has been slow, the field of phenomenological quantum gravity , which studies the possibility of experimental tests, has obtained increased attention. The most widely pursued possibilities for quantum gravity phenomenology include violations of Lorentz invariance , imprints of quantum gravitational effects in the cosmic microwave background in particular its polarization , and decoherence induced by fluctuations in the space-time foam.
- Theory of gravitational interactions (eBook, ) [theranchhands.com].
- Quantum gravity - Wikipedia!
- Warum ist Demografie, Alterung und Gesundheit ein wichtiges Thema für das Gesundheitsmanagement? (German Edition).
- .
- .
The BICEP2 experiment detected what was initially thought to be primordial B-mode polarization caused by gravitational waves in the early universe. Had the signal in fact been primordial in origin, it could have been an indication of quantum gravitational effects, but it soon transpired that the polarization was due to interstellar dust interference.
From Wikipedia, the free encyclopedia. This article may contain excessive or inappropriate references to self-published sources. Please help improve it by removing references to unreliable sources , where they are used inappropriately. June Learn how and when to remove this template message.
What verifiable predictions does any theory of quantum gravity make? Introduction to Quantum Mechanics. University of Chicago Press. Feynman Lectures on Gravitation.
Find a copy online
Quantum Field Theory in a Nutshell second ed. The road to reality: Geons, Black Holes, and Quantum Foam: A Life in Physics. Reviews of Modern Physics. Recent Developments in General Relativity. General Relativity and Gravitation. Approaches to Quantum Gravity. Classical and Quantum Gravity. Phase transitions and renormalization group. Three Roads to Quantum Gravity. Pages — are annotated references and guide for further reading. Modern Quantum Mechanics 2 ed.
Progress of Theoretical Physics Supplement. A First Course in String Theory. An Introduction to the Bosonic String. Superstring Theory and Beyond. Four Lectures on M-Theory. International Journal of Modern Physics A. Approaches to Fundamental Physics. Lecture Notes in Physics. Living Reviews in Relativity. From Classical to Quantum. International Journal of Theoretical Physics. In Hawking, Stephen W. Classical and Quantum Gravity: Theory, Analysis and Applications.
Bunch—Davies vacuum Hawking radiation Semiclassical gravity Unruh effect. Bosonic string theory M-theory Supergravity Superstring theory. Loop quantum gravity Wheeler—DeWitt equation. Causal dynamical triangulation Causal sets Noncommutative geometry Spin foam Group field theory Superfluid vacuum theory Twistor theory Dual graviton.
Theory of gravitational interactions
Newton's law of universal gravitation History of gravitational theory. Classical theories of gravitation Quantum gravity Theory of everything. Kaluza—Klein theory Dilaton Supergravity. Principle of relativity Galilean relativity Galilean transformation Special relativity Doubly special relativity. Time dilation Mass—energy equivalence Length contraction Relativity of simultaneity Relativistic Doppler effect Thomas precession Ladder paradox Twin paradox. Light cone World line Minkowski diagram Biquaternions Minkowski space. Equivalence principle Riemannian geometry Penrose diagram Geodesics Mach's principle.
Black hole Event horizon Singularity Two-body problem Gravitational waves: Brans—Dicke theory Kaluza—Klein Quantum gravity. String theory Loop quantum gravity Causal dynamical triangulation Canonical quantum gravity Superfluid vacuum theory Twistor theory. Introduction History timeline Glossary Classical mechanics Old quantum theory.