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Related papers: Prescriptions in Loop Quantum Cosmology: A compara…

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Quantum corrections of certain types and relevant in certain regimes can be summarised in terms of an effective action calculable, in principle, from the underlying theory. The demands of symmetries, local form of terms and dimensional…

General Relativity and Quantum Cosmology · Physics 2009-04-17 Ghanashyam Date , Sandipan Sengupta

Homogeneous cosmological models with non-vanishing intrinsic curvature require a special treatment when they are quantized with loop quantum cosmological methods. Guidance from the full theory which is lost in this context can be replaced…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald , Ghanashyam Date , Kevin Vandersloot

In this article, we review the use of numerical techniques to obtain solutions for the quantum Hamiltonian constraint in loop quantum cosmology (LQC). First, we summarize the basic features of LQC, and describe features of the constraint…

General Relativity and Quantum Cosmology · Physics 2012-01-04 David Brizuela , Daniel Cartin , Gaurav Khanna

One of critical components of Loop Quantum Gravity (LQG) and Cosmology (LQC) -- Thiemann regularization procedure is non-unique. Different choices of particular prescriptions lead to models which differ in both mathematical structure and…

General Relativity and Quantum Cosmology · Physics 2022-12-26 Maciej Kowalczyk , Tomasz Pawłowski

Quantum cosmology is the quantum theory of the entire universe. Although strange at first sight, it is appropriate because (1) our world appears to be fundamentally quantum, (2) the classical description of gravity breaks down at…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Don N. Page

Quantum lithography promises, in principle, unlimited feature resolution, independent of wavelength. However, in the literature at least two different theoretical descriptions of quantum lithography exist. They differ in to which extent…

Quantum Physics · Physics 2011-08-22 Christian Kothe , Gunnar Björk , Shuichiro Inoue , Mohamed Bourennane

Polymer quantization was discovered during the construction of Loop Quantum Cosmology. For the simplest quantum theory of one degree of freedom, the implications for dynamics were studied for the harmonic oscillator as well as some other…

General Relativity and Quantum Cosmology · Physics 2013-03-19 Ghanashyam Date , Nirmalya Kajuri

The polymer quantization of cosmological backgrounds provides an alternative path to the original Wheeler-de Witt (WdW) quantum cosmology, based on a different representation the commutation relations of the canonical variables. This…

General Relativity and Quantum Cosmology · Physics 2019-09-11 Jibril Ben Achour , Etera R. Livine

Ambiguities of the so-called Thiemann regularization in Loop Quantum Cosmology lead to freedom in how to construct a particular quantization prescription. So far three distinct examples of such have been proposed in the literature. For two…

General Relativity and Quantum Cosmology · Physics 2021-12-16 Maciej Kowalczyk

The indeterminism of quantum mechanics generally permits the independent specification of both an initial and a final condition on the state. Quantum pre-and-post-selection of states opens up a new, experimentally testable, sector of…

Quantum Physics · Physics 2015-06-17 Paul Davies

Quantum cosmology has traditionally been studied at the level of symmetry-reduced minisuperspace models, analyzing the behavior of wave functions. However, in the absence of a complete full setting of quantum gravity and detailed knowledge…

General Relativity and Quantum Cosmology · Physics 2012-09-18 Martin Bojowald

We use the method of embedding a subsystem (i.e. its observable algebra) into a larger quantum system to extract a cosmological sector from full Loop Quantum Gravity. The application of this method provides a setting for a systematic study…

General Relativity and Quantum Cosmology · Physics 2007-11-08 Tim A. Koslowski

Distance metrics and their nonlinear variant play a crucial role in machine learning based real-world problem solving. We demonstrated how Euclidean and cosine distance measures differ not only theoretically but also in real-world medical…

Machine Learning · Computer Science 2021-02-25 Der-Chen Chang , Ophir Frieder , Chi-Feng Hung , Hao-Ren Yao

This papers offers a critical discussion on the procedure by which Loop Quantum Cosmology (LQC) is constructed from the full Loop Quantum Gravity (LQG) theory. Revising recent issues in preserving SU(2) symmetry when quantizing the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Francesco Cianfrani , Giovanni Montani

Since there are quantization ambiguities in constructing the Hamiltonian constraint operator in isotropic loop quantum cosmology, it is crucial to check whether the key features of loop quantum cosmology, such as the quantum bounce and…

General Relativity and Quantum Cosmology · Physics 2009-04-28 Jinsong Yang , You Ding , Yongge Ma

Quantum gravity is sometimes considered as a kind of metaphysical speculation. In this review, we show that, although still extremely difficult to reach, observational signatures can in fact be expected. The early universe is an invaluable…

General Relativity and Quantum Cosmology · Physics 2015-06-17 A. Barrau , T. Cailleteau , J. Grain , J. Mielczarek

The separate-universe approach provides an effective description of cosmological perturbations at large scales, where the universe can be described by an ensemble of independent, locally homogeneous and isotropic patches. By reducing the…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-13 Danilo Artigas , Julien Grain , Vincent Vennin

This is the first paper of a series dedicated to LQG coherent states and cosmology. The concept is based on the effective dynamics program of Loop Quantum Cosmology, where the classical dynamics generated by the expectation value of the…

General Relativity and Quantum Cosmology · Physics 2019-11-14 Andrea Dapor , Klaus Liegener

The path-integral formulation of quantum cosmology with a massless scalar field as a sum-over-histories of volume transitions is discussed, with particular but non-exclusive reference to loop quantum cosmology. Exploiting the analogy with…

General Relativity and Quantum Cosmology · Physics 2011-07-08 Gianluca Calcagni , Steffen Gielen , Daniele Oriti

Volume operators measuring the total volume of space in a loop quantum theory of cosmological models are constructed. In the case of models with rotational symmetry an investigation of the Higgs constraint imposed on the reduced connection…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Martin Bojowald