English
Related papers

Related papers: Euclidean volume fluctuations in de Sitter quantum…

200 papers

In the recent article Phys. Rev. D 100, no. 4, 043533 (2019) a compact phase space generalization of the flat de Sitter cosmology has been proposed. The main advantages of the compactification is that physical quantities are bounded, and…

General Relativity and Quantum Cosmology · Physics 2021-06-09 Danilo Artigas , Sean Crowe , Jakub Mielczarek

We propose a theory of quantum gravity which formulates the quantum theory as a nonperturbative path integral, where each spacetime history appears with a weight given by the exponentiated Einstein-Hilbert action of the corresponding causal…

General Relativity and Quantum Cosmology · Physics 2010-05-12 J. Ambjorn , J. Jurkiewicz , R. Loll

We study quantum gravity on $dS_{3}$ using the Chern-Simons formulation of three -dimensional gravity. We derive an exact expression for the partition function for quantum gravity on $dS_{3}$ in a Euclidean path integral approach. We show…

High Energy Physics - Theory · Physics 2009-11-07 T. R. Govindarajan , R. K. Kaul , V. Suneeta

Classical gravity coupled to a CFT$_4$ (matter) is considered. The effect of the quantum dynamics of matter on gravity is studied around maximally symmetric spaces (flat, de Sitter and Anti de Sitter). The structure of the graviton…

General Relativity and Quantum Cosmology · Physics 2023-12-11 Jewel K. Ghosh , Elias Kiritsis , Francesco Nitti , Valentin Nourry

We propose that the underlying context of holographic duality and the Ryu-Takayanagi formula is that the volume measure of spacetime is a probability measure constrained by quantum dynamics. We define quantum stochastic processes using…

High Energy Physics - Theory · Physics 2024-01-17 S. Josephine Suh

We briefly overview the development of Euclidean quantum gravity in four dimensions regarded as a branch of statistical mechanics of discretized random manifolds.

High Energy Physics - Lattice · Physics 2008-02-03 A. Krzywicki

We present a detailed analysis of a quantum model for Loop Quantum Cosmology based on strict application of the Thiemann regularization algorithm for the Hamiltonian in Loop Quantum Gravity, extending the results presented previously in our…

General Relativity and Quantum Cosmology · Physics 2019-10-09 Mehdi Assanioussi , Andrea Dapor , Klaus Liegener , Tomasz Pawlowski

The quantum nature of the Big Bang is reexamined in the framework of Loop Quantum Cosmology. The strict application of a regularization procedure to the Hamiltonian, originally developed for the Hamiltonian in loop quantum gravity, leads to…

General Relativity and Quantum Cosmology · Physics 2018-08-29 Mehdi Assanioussi , Andrea Dapor , Klaus Liegener , Tomasz Pawłowski

Semiclassical gravity predicts that de Sitter space has a finite entropy. We suggest a picture for Euclidean de Sitter space in string theory, and use the AdS/CFT correspondence to argue that de Sitter entropy can be understood as the…

High Energy Physics - Theory · Physics 2010-05-28 Vijay Balasubramanian , Petr Horava , Djordje Minic

We consider the quantization of space-times which can possess different topologies within a symmetry reduced version of Wheeler-DeWitt theory. The quantum states are defined from a natural decomposition as an outer-product of a topological…

General Relativity and Quantum Cosmology · Physics 2014-04-17 Johan Brannlund , Andrew DeBenedictis , Alison Lauman

One can try to define the theory of quantum gravity as the sum over geometries. In two dimensions the sum over {\it Euclidean} geometries can be performed constructively by the method of {\it dynamical triangulations}. One can define a {\it…

General Relativity and Quantum Cosmology · Physics 2017-08-23 J. Ambjorn

Motivated by the prospect of constraining microscopic models, we calculate the exact one-loop corrected de Sitter entropy (the logarithm of the sphere partition function) for every effective field theory of quantum gravity, with particles…

High Energy Physics - Theory · Physics 2022-02-22 Dionysios Anninos , Frederik Denef , Y. T. Albert Law , Zimo Sun

We discuss some general properties of quantum gravity in De Sitter space. It has been argued that the Hilbert space is of finite dimension. This suggests a macroscopic argument that General Relativity cannot be quantized -- unless it is…

High Energy Physics - Theory · Physics 2007-05-23 Edward Witten

We show that the quantum universe emerging from a nonperturbative, Lorentzian sum-over-geometries can be described with high accuracy by a four-dimensional de Sitter spacetime. By a scaling analysis involving Newton's constant, we establish…

High Energy Physics - Theory · Physics 2009-12-15 J. Ambjorn , A. Gorlich , J. Jurkiewicz , R. Loll

In simple -- but selected -- quantum systems, the probability distribution determined by the ground state wave function is infinitely divisible. Like all simple quantum systems, the Euclidean temporal extension leads to a system that…

Quantum Physics · Physics 2007-05-23 John R. Klauder

We present a possibility of coupling a point-like, non-singular, mass distribution to four-dimensional quantum gravity in the nonperturbative setting of causal dynamical triangulations (CDT). In order to provide a point of comparison for…

General Relativity and Quantum Cosmology · Physics 2010-09-16 Igor Khavkine , Renate Loll , Paul Reska

We consider Einstein gravity with positive cosmological constant coupled with higher spin interactions and calculate Euclidean path integral perturbatively. We confine ourselves to the static patch of the 3 dimensional de Sitter space. This…

High Energy Physics - Theory · Physics 2015-07-22 Rudranil Basu

Gaussian distributions can be generalized from Euclidean space to a wide class of Riemannian manifolds. Gaussian distributions on manifolds are harder to make use of in applications since the normalisation factors, which we will refer to as…

Probability · Mathematics 2023-02-16 Simon Heuveline , Salem Said , Cyrus Mostajeran

We sketch the construction of a quantum model of 3 dimensional de Sitter space, based on the Covariant Entropy Principle and the observation that semi-classical physics suggests the possibility of a consistent theory of a finite number of…

High Energy Physics - Theory · Physics 2024-01-31 Sidan A , Tom Banks , Willy Fischler

A Euclidean formulation of relativistic quantum mechanics is discussed. Representations of the Hilbert space inner product and Poincar\'e generators are all expressed in terms of Euclidean space-time variables. The formulation does not…

High Energy Physics - Lattice · Physics 2018-09-10 W. N. Polyzou , Gordon Aiello , Philip Kopp