English
Related papers

Related papers: Pre-inflationary dynamics in loop quantum cosmolog…

200 papers

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

We make use of possible high energy correction to the Friedmann equation to implement the bounce and study the behavior of massive scalar field before and after bounce semianalytically and numerically. We find that the slow-roll inflation…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Yun-Song Piao , Yuan-Zhong Zhang

We develop a consistent analytic approach to determine the conditions under which slow roll inflation can arise when the inflaton is the same scalar field that is responsible for the bounce in Loop Quantum Cosmology (LQC). We find that the…

General Relativity and Quantum Cosmology · Physics 2019-11-04 Anshuman Bhardwaj , Edmund J. Copeland , Jorma Louko

We investigate the imprints on the angular power spectra of cosmological perturbations of a pre-inflationary bounce phase, as described by the hybrid and dressed metric approaches to loop quantum cosmology. For this purpose, we derive a new…

General Relativity and Quantum Cosmology · Physics 2026-05-15 Almudena Guillén , Kai Langer , Guillermo A. Mena Marugán , Niklas Rodenbücher , Antonio Vicente-Becerril

During inflationary preheating, the energy stored in the inflaton field is rapidly converted into excitations of other entropy fields. This stage is characterized by exponential particle production due to parametric resonance and is…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-15 Jie Jiang , Qiuyue Liang , Yi-Fu Cai , Damien A. Easson , Yang Zhang

There is a wide consensus on the correct dynamics of the background in loop quantum cosmology. In this article we make a systematic investigation of the duration of inflation by varying what we think to be the most important "unknowns" of…

General Relativity and Quantum Cosmology · Physics 2017-04-19 Killian Martineau , Aurélien Barrau , Susanne Schander

Loop quantum cosmology provides an efficient framework to study the evolution of the Universe beyond the classical Big Bang paradigm. Because of holonomy corrections, the singularity is replaced by a "bounce". The dynamics of the background…

General Relativity and Quantum Cosmology · Physics 2015-03-13 Jakub Mielczarek , Thomas Cailleteau , Julien Grain , Aurelien Barrau

We study the problem of initial conditions for slow-roll inflation along a plateau-like scalar potential within the framework of fluctuation-dissipation dynamics. We consider, in particular, that inflation was preceded by a…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-09 Mar Bastero-Gil , Arjun Berera , Robert Brandenberger , Ian G. Moss , Rudnei O. Ramos , Joao G. Rosa

The prediction of a phase of inflation whose number of e-folds is constrained is an important feature of loop quantum cosmology. This work aims at giving some elementary clarifications on the role of the different hypotheses leading to this…

General Relativity and Quantum Cosmology · Physics 2017-07-05 Boris Bolliet , Aurélien Barrau , Killian Martineau , Flora Moulin

Loop quantum cosmology is considered in inflation era. A slow roll scalar field solution with power law potential is presented in the neighborhood of transition time, i.e. when the universe enters inflation phase from super-inflation. The…

General Relativity and Quantum Cosmology · Physics 2017-03-08 H. Mohseni Sadjadi

Recently the background independent nonperturbative quantization technique has been extended to theories of gravity and the corresponding quantum effective cosmology has been derived, which provides us with necessary avenue to explore the…

General Relativity and Quantum Cosmology · Physics 2020-03-03 Manabendra Sharma , Tao Zhu , Anzhong Wang

In loop quantum cosmology (LQC), the initial singularity is replaced by a quantum bounce, leading to a universal post-bounce evolution characterized by three distinct epochs: bouncing, transition, and slow-roll inflation, before the hot…

General Relativity and Quantum Cosmology · Physics 2025-12-03 Yogesh , Bao-Fei Li , Mayukh R. Gangopadhyay , Anzhong Wang

We consider the effects on the primordial power spectrum of a period of radiation-dominated expansion prior to the inflationary era. If inflation lasts a total of only 60 e-folds or so, the boundary condition for quantum modes cannot be…

Astrophysics · Physics 2008-11-26 Brian A. Powell , William H. Kinney

A warm inflationary universe model in loop quantum cosmology is studied. In general we discuss the condition of inflation in this framework. By using a chaotic potential, $V(\phi)\propto \phi^2$, we develop a model where the dissipation…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Ramon Herrera

We develop a quantum-cosmological framework in which the inflationary potential emerges from the structure of the wave function of the universe rather than being postulated. Starting from the Wheeler-DeWitt equation for a flat…

General Relativity and Quantum Cosmology · Physics 2025-10-07 Gerasimos Kouniatalis

Inflation in the early Universe is one of the most promising probes of gravity in the high-energy regime. However, observable scales give access to a limited window in the inflationary dynamics. In this essay, we argue that quantum…

High Energy Physics - Theory · Physics 2017-11-22 Robert J. Hardwick , Vincent Vennin , David Wands

This thesis is dedicated to studying cosmological inflation, which is a period of accelerated expansion in the very early Universe that is required to explain the observed anisotropies in the cosmic microwave background. Inflation, when…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-02 Chris Pattison

We consider a non-minimally coupled inflaton, in a higher order curvature background, leading to a potential which evolves with the curvature scalar of the Universe, and which describes two regimes. The first one is a de Sitter phase, where…

High Energy Physics - Phenomenology · Physics 2015-03-13 Jean Alexandre

We consider the classical evolution of the inflaton field $\phi(t)$ and the Hubble parameter $H(t)$ in homogeneous and isotropic single-field inflation models. Under an extremely broad assumption, we show that the universe generically…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 W. J. Handley , S. D. Brechet , A. N. Lasenby , M. P. Hobson

We conduct a (pre-)inflationary dynamics study within the framework of a simple noncommutative extension of effective loop quantum cosmology -- put forward recently by the authors -- which preserves its key features (in particular, the…

General Relativity and Quantum Cosmology · Physics 2023-08-04 Luis Rey Díaz-Barrón , Abraham Espinoza-García , S. Pérez-Payán , J. Socorro