English
Related papers

Related papers: Towards A Background Independent Quantum Gravity

200 papers

Although it's widely believed that gravity should have a quantum nature like every other force, the conceptual obstacles to constructing a quantum theory of gravity compel us to explore other perspectives. Gravity is not like any other…

General Relativity and Quantum Cosmology · Physics 2024-07-30 Jonathan Oppenheim

Loop quantum gravity is a perspective candidate for the quantum theory of gravity. However, there is a conceptual controversy in it: having started from the Einstein-Hilbert action and describing spacetime without matter, we can hardly…

General Relativity and Quantum Cosmology · Physics 2026-02-10 Mikhail Altaisky

Gravity-induced quantum interference is an experiment that exhibits how a gravitational effect appears in quantum mechanics. In this famous experiments gravity was added to the system just classically. In our study we do the related…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Mohammad A. Ganjali , Zainab Sedaghatmanesh

We illustrate a general reconstruction procedure for mimetic gravity. Focusing on a bouncing cosmological background, we derive general properties that must be satisfied by the function $f(\Box\phi)$ implementing the limiting curvature…

General Relativity and Quantum Cosmology · Physics 2019-05-10 Marco de Cesare

Quantum gravity was born as that branch of modern theoretical physics that tries to unify its guiding principles, i.e., quantum mechanics and general relativity. Nowadays it is providing new insight into the unification of all fundamental…

High Energy Physics - Theory · Physics 2011-08-17 Giampiero Esposito

In the present discussion Background Independent framework of Quantum Mechanics and its possible implications in the studies of gravity and Physics at short distance are addressed. The expression of the metric of quantum state space…

General Physics · Physics 2009-01-09 Aalok

A non-perturbative and background-independent quantum formulation of quadratic gravity is provided. A canonical quantization procedure introduced in previous works, named after Dirac and Pauli, is here applied to quadratic gravity to…

High Energy Physics - Theory · Physics 2024-08-05 Alberto Salvio

We calculate deviations in cosmological observables as a function of parameters in a class of connection-based models of quantum gravity. In this theory non-trivial modifications to the background cosmology can occur due to a distortion of…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 Michael W. Toomey , Savvas Koushiappas , Bruno Alexandre , João Magueijo

We study how physical information can be extracted from a background independent quantum system. We use an extremely simple `minimalist' system that models a finite region of 3d euclidean quantum spacetime with a single equilateral…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Carlo Rovelli , Daniele Colosi , Luisa Doplicher , Winston Fairbairn , Leonardo Modesto , Karim Noui

Assuming the von Neumann algebra associated with a generic de Sitter observer is properly infinite (type III) we use Connes cocycle to identify the unique ( up to unitary equivalence) background independent dominant weight on an extended…

High Energy Physics - Theory · Physics 2023-11-06 Cesar Gomez

A scenario is outlined for quantum measurement, assuming that self-sustaining classicality is the consequence of an attractive gravitational self-interaction acting on massive bodies, and randomness arises already in the classical domain. A…

Quantum Physics · Physics 2007-05-23 Tamás Geszti

Contemporary research programs in fundamental physics appear to suggest that there could be two (physical) times---or none at all. This essay articulates these possibilities in the context of quantum gravity, and in particular of…

History and Philosophy of Physics · Physics 2020-09-14 Christian Wuthrich

The existence of a fundamental scale, a lower bound to any output of a position measurement, seems to be a model-independent feature of quantum gravity. In fact, different approaches to this theory lead to this result. The key ingredients…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Luis J. Garay

We review the present status of quantum-gravity phenomenology in relation to gravitational waves (GWs). The topic can be approached from two direction, a model-dependent one and a model-independent one. In the first case, we introduce some…

General Relativity and Quantum Cosmology · Physics 2021-10-07 Gianluca Calcagni

Quantum gravity is known to be mostly a kind of metaphysical speculation. In this brief essay, we try to argue that, although still extremely difficult to reach, observational signatures can in fact be expected. The early universe is an…

General Relativity and Quantum Cosmology · Physics 2012-06-07 Aurelien Barrau , Julien Grain

Several examples are known where quantum gravity effects resolve the classical big bang singularity by a bounce. The most detailed analysis has probably occurred for loop quantum cosmology of isotropic models sourced by a free, massless…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Martin Bojowald

We describe a theory amalgamating quantum theory and general relativity through the identification of a continuous 4-dimensional spacetime arena constructed from the substructures of a generalised multi-dimensional form for proper time. In…

General Physics · Physics 2020-10-07 David J. Jackson

The intersection of thermodynamics, quantum theory and gravity has revealed many profound insights, all the while posing new puzzles. In this article, we discuss an extension of equilibrium statistical mechanics and thermodynamics…

General Relativity and Quantum Cosmology · Physics 2019-08-13 Isha Kotecha

If gravity were an emergent phenomenon, some relativistic as well as non-relativistic speculations claim it is, then a certain emergence time scale tau_? would characterize it. We argue that the available experimental evidences have poor…

General Relativity and Quantum Cosmology · Physics 2014-11-19 Lajos Diósi

I briefly review the current status of quantum gravity. After giving some general motivations for the need of such a theory, I discuss the main approaches in quantizing general relativity: Covariant approaches (perturbation theory,…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Claus Kiefer