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Related papers: Loop Quantum Cosmology and Boundary Proposals

200 papers

This is an introduction to loop quantum cosmology (LQC) reviewing mini- and midisuperspace models as well as homogeneous and inhomogeneous effective dynamics.

General Relativity and Quantum Cosmology · Physics 2012-03-27 Kinjal Banerjee , Gianluca Calcagni , Mercedes Martín-Benito

We construct and study Loop Quantum Cosmology (LQC) when the Barbero-Immirzi parameter takes the complex value $\gamma=\pm i$. We refer to this new quantum cosmology as complex Loop Quantum Cosmology. We proceed in making an analytic…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Jibril Ben Achour , Julien Grain , Karim Noui

Boundary conditions play a crucial role in the path-integral approach to quantum gravity and quantum cosmology, as well as in the current attempts to understand the one-loop semiclassical properties of quantum field theories. Within this…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ivan G. Avramidi , Giampiero Esposito

An improved Hamiltonian constraint operator is introduced in loop quantum cosmology. Quantum dynamics of the spatially flat, isotropic model with a massless scalar field is then studied in detail using analytical and numerical methods. The…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Abhay Ashtekar , Tomasz Pawlowski , Parampreet Singh

We consider the quantum dynamics of a free nonrelativistic particle moving in a cavity and we analyze the effect of a rapid switching between two different boundary conditions. We show that this procedure induces, in the limit of infinitely…

Mathematical Physics · Physics 2018-02-15 Paolo Facchi , Giancarlo Garnero , Marilena Ligabò

Loop quantum cosmology in (b, v) variables, which is governed by a unit step size difference equation, is embedded into a full theory context based on similar variables. A full theory context here means a theory of quantum gravity arrived…

General Relativity and Quantum Cosmology · Physics 2016-05-20 Norbert Bodendorfer

Quantum mechanics in its presently known formulation requires an external classical time for its description. A classical spacetime manifold and a classical spacetime metric are produced by classical matter fields. In the absence of such…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. P. Singh

In this work, we consider effects of the dynamical vacuum in quantum cosmology in presence of a minimum length introduced by the GUP (generalized uncertainty principle) related to the modified commutation relation $[\hat{X},\hat{P}] :=…

General Relativity and Quantum Cosmology · Physics 2021-05-05 M. F. Gusson , A. Oakes O. Gonçalves , R. G. Furtado , J. C. Fabris , J. A. Nogueira

Quantum gravity has long been thought to be completely decoupled from experiments or observations. Although it is true that smoking guns are still missing, there are now serious hopes that quantum gravity phenomena might be tested. We…

General Relativity and Quantum Cosmology · Physics 2015-10-29 A. Barrau , J. Grain

In this topical review we discuss the connections between chaos, decoherence and quantum cosmology. We understand chaos as classical chaos in systems with a finite number of degrees of freedom, decoherence as environment induced decoherence…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Esteban Calzetta

The search for a consistent and empirically established quantum theory of gravity is among the biggest open problems of fundamental physics. The obstacles are of formal and of conceptual nature. Here, I address the main conceptual problems,…

General Relativity and Quantum Cosmology · Physics 2014-01-16 Claus Kiefer

This is an introductory set of lecture notes on quantum cosmology, given in 1995 to an audience with interests ranging from astronomy to particle physics. Topics covered: 1. Introduction: 1.1 Quantum cosmology and quantum gravity; 1.2 A…

General Relativity and Quantum Cosmology · Physics 2007-05-23 D. L. Wiltshire

We discuss the construction of wave packets resulting from the solutions of a class of Wheeler-DeWitt equations in Robertson-Walker type cosmologies. We present an ansatz for the initial conditions which leads to a unique determination of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. S. Gousheh , H. R. Sepangi

Motivated by previous works, we study semi-classical cosmological solutions and the wave function of the Wheeler-DeWitt equation in the Bose-Parker-Peleg model. We obtain the wave function of the universe satisfying the suitable boundary…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Wontae Kim , Edwin J. Son , Myung Seok Yoon

We follow the Feynman procedure to obtain a path integral formulation of loop quantum cosmology starting from the Hilbert space framework. Quantum geometry effects modify the weight associated with each path so that the effective measure on…

General Relativity and Quantum Cosmology · Physics 2011-01-25 Abhay Ashtekar , Miguel Campiglia , Adam Henderson

On the path towards quantum gravity, we find friction between temporal relations in quantum mechanics (QM) (where they are fixed and field-independent), and in general relativity (where they are field-dependent and dynamic). This paper aims…

General Relativity and Quantum Cosmology · Physics 2017-11-28 Henrique Gomes

As a canonical and generally covariant gauge theory, loop quantum gravity requires special techniques to derive effective actions or equations. If the proper constructions are taken into account, the theory, in spite of considerable…

General Relativity and Quantum Cosmology · Physics 2013-08-02 Martin Bojowald

On the basis that the universe is a closed quantum system with no external observers, we propose a paradigm in which the universe jumps through a series of stages. Each stage is defined by a quantum state, an information content, and rules…

Quantum Physics · Physics 2007-05-23 Jon Eakins , George Jaroszkiewicz

In loop quantum cosmology, the values of volume fluctuations and correlations determine whether the dynamics of an evolving state exhibits a bounce. Of particular interest are states that are supported only on either the positive or the…

General Relativity and Quantum Cosmology · Physics 2020-01-06 Martin Bojowald

This article presents an "in-a-nutshell" yet self-contained introductory review on loop quantum gravity (LQG) -- a background-independent, nonperturbative approach to a consistent quantum theory of gravity. Instead of rigorous and…

General Relativity and Quantum Cosmology · Physics 2014-12-30 Dah-Wei Chiou