Results 61 to 70 of about 467 (173)

Variational methods in loop quantum cosmology [PDF]

open access: yesEurophysics Letters (EPL), 2006
An action functional for the loop quantum cosmology difference equation is presented. It is shown that by guessing the general form of the solution and optimizing the action functional with respect to the parameters in the guessed solution one can obtain approximate solutions which are reasonably good.
Shojai, F., Shojai, A.
openaire   +3 more sources

Loop Quantum Cosmology: A cosmological theory with a view

open access: yesJournal of Physics: Conference Series, 2011
Loop Quantum Gravity is a background independent, nonperturbative approach to the quantization of General Relativity. Its application to models of interest in cosmology and astrophysics, known as Loop Quantum Cosmology, has led to new and exciting views of the gravitational phenomena that took place in the early universe, or that occur in spacetime ...
openaire   +3 more sources

Quantum Gravitational Non-Singular Tunneling Wavefunction Proposal

open access: yesPhysical Sciences Forum, 2023
It has recently been shown that the tunneling wavefunction proposal is consistent with loop quantum geometry corrections, including both holonomy and inverse scale factor corrections, in the gravitational part of a spatially closed isotropic model with a
Meysam Motaharfar, Parampreet Singh
doaj   +1 more source

Background Instability of Quintessence Model in Light of Entropy and Distance Conjecture

open access: yesFortschritte der Physik, Volume 74, Issue 6, June 2026.
ABSTRACT We apply the covariant entropy bound argument supporting the de Sitter swampland conjecture to the quintessence model, to find out the condition for the background to be unstable. More concretely, the background is unstable when the matter entropy given by the species number of the effective field theory increases more rapidly than the ...
Min‐Seok Seo
wiley   +1 more source

LOOP QUANTUM COSMOLOGY AND BOUNDARY PROPOSALS [PDF]

open access: yesThe Tenth Marcel Grossmann Meeting, 2006
For many years, the most active area of quantum cosmology has been the issue of choosing boundary conditions for the wave function of a universe. Recently, loop quantum cosmology, which is obtained from loop quantum gravity, has shed new light on this question.
Bojowald, M., Vandersloot, K.
openaire   +3 more sources

Restrictions on curved cosmologies in modified gravity from metric considerations

open access: yesPhysics Letters B, 2015
This study uses very simple symmetry and consistency considerations to put constraints on possible Friedmann equations for modified gravity models in curved spaces. As an example, it is applied to loop quantum cosmology.
Linda Linsefors, Aurelien Barrau
doaj   +1 more source

Counting Degrees of Freedom: A Method Applicable From Scalars to f(Q)$f(\mathbb {Q})$ Gravity and Beyond

open access: yesFortschritte der Physik, Volume 74, Issue 6, June 2026.
ABSTRACT We present a clear, step‐by‐step method for counting degrees of freedom and identifying constraints in general field theories. This approach, grounded in the works of Einstein, Hilbert, Cartan, Kuranishi, and, more recently, Seiler, is neither Lagrangian nor Hamiltonian in nature. Instead, it applies directly to the field equations. We offer a
Lavinia Heisenberg
wiley   +1 more source

On the uniqueness of kinematics of loop quantum cosmology [PDF]

open access: yesClassical and Quantum Gravity, 2012
The holonomy-flux algebra $\A$ of loop quantum gravity is known to admit a natural representation that is uniquely singled out by the requirement of covariance under spatial diffeomorphisms. In the cosmological context, the requirement of spatial homogeneity naturally reduces $\A$ to a much smaller algebra, $\A_{\rm Red}$, used in loop quantum ...
Ashtekar, Abhay, Campiglia, Miguel
openaire   +2 more sources

Alignment of the Starlings: Learning With Generative AI

open access: yesFuture Humanities, Volume 4, Issue 1, May 2026.
ABSTRACT I will argue that answers to normative questions concerning the place of generative AI in learning rest on answers to ontological questions regarding (1) precisely what is happening when a human ‘interacts’ with generative AI and (2) What is distinctive about organic learning as opposed to currently existing ‘machine learning’ (3) What is the ...
Sean Watson
wiley   +1 more source

Loop quantum cosmology gravitational baryogenesis [PDF]

open access: yesEPL (Europhysics Letters), 2016
Loop Quantum Cosmology is an appealing quantum completion of classical cosmology, which brings along various theoretical features which in many cases offer remedy or modify various classical cosmology aspects. In this paper we address the gravitational baryogenesis mechanism in the context of Loop Quantum Cosmology. As we demonstrate, when Loop Quantum
Odintsov, S. D., Oikonomou, V. K.
openaire   +2 more sources

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