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Related papers: Exploring the pre-inflationary dynamics in loop qu…

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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

Inflationary cosmology proposes that the early Universe undergoes accelerated expansion, driven, in simple scenarios, by a single scalar field, or inflaton. The form of the inflaton potential determines the initial spectra of density…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 Richard Easther , Benedict Bahr-Kalus , David Parkinson

In this article we explore the pre-inflationary background dynamics of an FLRW universe sourced by a scalar field with monodromy potential in LQC framework. In particular we calculate the number of e-folds, $N_{inf}$, produced during the…

General Relativity and Quantum Cosmology · Physics 2018-11-15 Manabendra Sharma , M. Shahalam , Wu Qiang , Anzhong Wang

Nonlinear electrodynamics with two dimensional parameters is studied. The range of electromagnetic fields when principles of causality, unitarity and the classical stability hold, are obtained. A singularity of the electric field at the…

General Relativity and Quantum Cosmology · Physics 2022-12-27 S. I. Kruglov

The Planck collaboration has provided us rich information about the early universe, and a host of new observational missions will soon shed further light on the `anomalies' that appear to exist on the largest angular scales. From a quantum…

General Relativity and Quantum Cosmology · Physics 2015-11-18 Abhay Ashtekar , Aurelien Barrau

A very simple non-singular inflationary model is presented where the unique matter content is a radiation fluid. The model slowly contracts from a very large, almost empty and flat spacetime and realizes a bounce. It is then launched to a…

General Relativity and Quantum Cosmology · Physics 2024-03-08 Piero A. P. Molinari , Paola C. M. Delgado , Rodrigo F. Pinheiro , Nelson Pinto-Neto

We provide an exhaustive numerical exploration of the predictions of loop quantum cosmology (LQC) with a post-bounce phase of inflation for the primordial power spectrum of scalar and tensor perturbations. We extend previous analysis by…

General Relativity and Quantum Cosmology · Physics 2015-12-30 Ivan Agullo , Noah A. Morris

While loop quantum cosmology (LQC) predicts a robust quantum bounce of the background evolution of a Friedmann-Robertson-Walker (FRW) spacetime prior to the standard slow-roll inflation, whereby the big bang singularity is resolved, there…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Qiang Wu , Tao Zhu , Anzhong Wang

Recent work in quantum loop cosmology suggests the universe undergoes a bounce when evolving from a previous collapsing phase. However, with non-inflationary matter sources, the scenario appears to strongly violate the holography bound…

General Relativity and Quantum Cosmology · Physics 2012-12-19 D. H. Coule

Recent observations of Type Ia supernovae provide evidence for the acceleration of our universe, which leads to the possibility that the universe is entering an inflationary epoch. We simulate it under a ``big bounce'' model, which contains…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Beili Wang , Hongya Liu , Lixin Xu

We present the method of describing an evolution in quantum cosmology in the framework of the reduced phase space quantization of loop cosmology. We apply our method to the flat Friedman-Robertson-Walker model coupled to a massless scalar…

General Relativity and Quantum Cosmology · Physics 2012-03-06 Jakub Mielczarek , Wlodzimierz Piechocki

We discuss the asymmetry of cosmic background evolution in time with respect to the quantum bounce in the Loop Quantum Cosmology (LQC), employing the value of scalar field at the bounce $\phi_{\rm B}$. We use the Chaotic and the $R^2$…

General Relativity and Quantum Cosmology · Physics 2019-07-03 Wen-Hsuan Lucky Chang , Jiun-Huei Proty Wu

This paper consider an universe dominated by baryonic matter, radiation and a nonminimally coupled massive scalar field under the action of a symmetry breaking potential. Inflation occurs naturally with appropriated slow-roll values. The…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-02 S. H. Pereira

In loop quantum cosmology there may be a super-inflation phase in the very early universe, in which a single scalar field with a negative power-law potential $V= -M^4(\phi/M)^\beta$ plays important roles. Since the effective horizon…

General Relativity and Quantum Cosmology · Physics 2009-11-19 Masahiro Shimano , Tomohiro Harada

In this work, we investigate the (pre)-inflationary dynamics of a flat, homogeneous, and isotropic universe governed by the Starobinsky potential within the framework of noncommutative effective loop quantum cosmology. The field equations…

General Relativity and Quantum Cosmology · Physics 2025-12-05 Luis Rey Díaz-Barrón , Abraham Espinoza-García , Sinuhé Pérez-Payán , José Socorro

Within the framework of loop quantum cosmology, there exists a semi-classical regime where spacetime may be approximated in terms of a continuous manifold, but where the standard Friedmann equations of classical Einstein gravity receive…

General Relativity and Quantum Cosmology · Physics 2009-11-10 James E. Lidsey

Inflationary and bouncing scenarios are two frameworks that provide the mechanism to overcome the horizon problem as well as generate the primordial perturbations. In this work, we investigate the conservation of perturbations in…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-07 Rathul Nath Raveendran

Positively-curved, oscillatory universes are studied within the context of Loop Quantum Cosmology subject to a consistent semi-classical treatment. The semi-classical effects are reformulated in terms of an effective phantom fluid with a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 James E. Lidsey , David J. Mulryne , N. J. Nunes , Reza Tavakol

By incorporating quantum aspects of gravity, Loop Quantum Cosmology (LQC) provides a self-consistent extension of the inflationary scenario, allowing for modifications in the primordial inflationary power spectrum with respect to the…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-01 Micol Benetti , Leila Graef , Rudnei O. Ramos

We study the quantum evolution of the early universe, its semi-classical analogue together with inflationary regime, in view of a generalized modified theory of gravity. The action is built by supplementing the non-minimally coupled…

High Energy Physics - Theory · Physics 2021-01-11 Ranajit Mandal , Dalia Saha , Mohosin Alam , Abhik Kumar Sanyal
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