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Related papers: Loop quantum cosmology and slow roll inflation

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We explore a reduced phase space quantization of loop quantum cosmology (LQC) for a spatially flat FLRW universe filled with reference fields and an inflaton field in a Starobinsky inflationary potential. We consider three separate cases in…

General Relativity and Quantum Cosmology · Physics 2021-01-04 Kristina Giesel , Bao-Fei Li , Parampreet Singh

In this paper, we investigate the dynamics of pre-inflation with Hilltop potential in the framework of loop quantum cosmology. The initial conditions of inflaton field at the quantum bounce is categorized into two classes, first one is…

General Relativity and Quantum Cosmology · Physics 2023-02-03 M. Shahalam , Kuralay Yesmakhanova , Zhanar Umurzakhova

Alternative scenarios to the Big Bang singularity have been subject of intense research for several decades by now. Most popular in this sense have been frameworks were such singularity is replaced by a bounce around some minimal…

General Relativity and Quantum Cosmology · Physics 2017-09-25 Emanuele Alesci , Gioele Botta , Francesco Cianfrani , Stefano Liberati

Quantum gravity is expected to be necessary in order to understand situations where classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e. the fact that the backward evolution…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Martin Bojowald

A popular science article designed to introduce people familiar with basic cosmological nomenclature with models alternative to cosmological inflation. The paper briefly discusses the modern view of the Big Bang model, inflation (both its…

Popular Physics · Physics 2024-04-30 Marcin Postolak

A well-motivated extension of higher order holonomy corrections in loop quantum cosmology (LQC) for the $k=0$ Friedmann-Robertson-Walker model is investigated at the level of heuristic effective dynamics. It reveals that the quantum bounce…

General Relativity and Quantum Cosmology · Physics 2009-03-24 Dah-Wei Chiou , Li-Fang Li

We study the loop quantum cosmology of a flat Friedmann-Lemaitre-Robertson-Walker space-time with a Maxwell field. We show that many of the qualitative properties derived for the case of a massless scalar field also hold for a Maxwell…

General Relativity and Quantum Cosmology · Physics 2015-01-07 Tomasz Pawlowski , Roberto Pierini , Edward Wilson-Ewing

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

The slow rolling inflation is dual to the random walk of conformal zero-mode. The 2 dimensional Fokker-Planck theory predicts the slow roll parameters of 4d inflation theory. The O(N) enhancements of the two point functions, N is the…

High Energy Physics - Theory · Physics 2023-05-02 Yoshihisa Kitazawa

Loop quantum cosmology is an application of recent developments for a non-perturbative and background independent quantization of gravity to a cosmological setting. Characteristic properties of the quantization such as discreteness of…

Astrophysics · Physics 2009-11-13 Martin Bojowald

Inflation has been the leading early universe scenario for two decades, and has become an accepted element of the successful `cosmic concordance' model. However, there are many puzzling features of the resulting theory. It requires both…

High Energy Physics - Theory · Physics 2009-11-10 Neil Turok , Paul J. Seinhardt

The Dapor-Liegener model of Loop Quantum Cosmology (LQC), which depicts an emergent universe from a de Sitter regime in the contracting phase is studied from the mathematical viewpoint of dynamical systems and compared with the standard…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Jaume de Haro

We discuss the cosmological inflation in the context of $f(Q)$ non-metric gravity, where $Q$ is the non-metric scalar. After introducing conformal transformations for $f(Q)$ gravity, we first focus on the potential-slow-roll inflation by…

General Relativity and Quantum Cosmology · Physics 2022-09-23 Salvatore Capozziello , Mehdi Shokri

A proposal is made for the quantum state of the universe that has an initial state that is macroscopically time symmetric about a homogeneous, isotropic bounce of extremal volume and that at that bounce is microscopically in the ground…

High Energy Physics - Theory · Physics 2015-05-13 Don N. Page

Anomaly-free perturbations of loop quantum cosmology reveal a deformed space-time structure, in which the signature changes when the energy density is $\rho=\rho_c/2$. Furthermore, in loop quantum cosmology, one can obtain an effective…

General Relativity and Quantum Cosmology · Physics 2015-11-19 Long Chen , Jian-Yang Zhu

We present the detailed analyses of five-dimensional loop quantum Kaluza-Klein cosmology based on the symmetric reduction of the connection formulation of the full theory. The previous results in a particular scenario are extended to more…

General Relativity and Quantum Cosmology · Physics 2026-05-28 Shengzhi Li , Yongge Ma , Faqiang Yuan , Xiangdong Zhang

We examine the nature of the cosmological big-bounce (BB) transition within the loop geometry underlying Loop Quantum Cosmology (LQC) at classical and quantum levels. Our canonical quantization method is an alternative to the standard LQC.…

General Relativity and Quantum Cosmology · Physics 2015-05-14 Wlodzimierz Piechocki

Loop quantum cosmology (LQC) is used to provide concrete evidence in support of the general paradigm underlying spin foam models (SFMs). Specifically, it is shown that: i) the physical inner product in the timeless framework equals the…

General Relativity and Quantum Cosmology · Physics 2009-12-10 Abhay Ashtekar , Miguel Campiglia , Adam Henderson

The quantum cosmology of the flat Friedmann-Lema{\^i}tre-Robertson-Walker Universe, filled with a scalar field, is considered in the de Broglie-Bohm (dBB) interpretation framework. A stiff-matter quantum bounce solution is obtained. The…

General Relativity and Quantum Cosmology · Physics 2023-07-24 G. S. Vicente , Rudnei O. Ramos , Vitória N. Magalhães

Loop quantum cosmology (LQC) provides a resolution of the classical big bang singularity in the deep Planck era. The evolution, prior to the usual slow-roll inflation, naturally generates excited states at the onset of the slow-roll…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 Tao Zhu , Anzhong Wang , Klaus Kirsten , Gerald Cleaver , Qin Sheng