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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

We investigate the implications of different quantization approaches in Loop Quantum Cosmology for the primordial power spectrum of tensor modes. Specifically, we consider the hybrid and dressed metric approaches to derive the effective…

General Relativity and Quantum Cosmology · Physics 2024-09-30 Guillermo A. Mena Marugán , Antonio Vicente-Becerril , Jesús Yébana Carrilero

This work is an analytical study of the main differences between classical inflationary effects of a fast-roll regime and imprints of hybrid Loop Quantum Cosmology (LQC) on the primordial power spectrum. Effective LQC solutions of…

General Relativity and Quantum Cosmology · Physics 2021-10-01 Beatriz Elizaga Navascués , Guillermo A. Mena Marugán

We study the evolution of spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker universe for chaotic and Starobinsky potentials in the framework of modified loop quantum cosmologies. These models result in a non-singular bounce as in loop…

General Relativity and Quantum Cosmology · Physics 2019-09-18 Bao-Fei Li , Parampreet Singh , Anzhong Wang

A self-consistent pre-inflationary extension of the inflationary scenario with the Starobinsky potential, favored by Planck data, is studied using techniques from loop quantum cosmology (LQC). The results are compared with the quadratic…

General Relativity and Quantum Cosmology · Physics 2016-05-25 Béatrice Bonga , Brajesh Gupt

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 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

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

The lack of correlations on the large scale cosmic microwave background (CMB) anisotropy provides a potential window to probe beyond the standard inflationary scenario. In this paper, we investigate the primordial power spectrum based on…

General Relativity and Quantum Cosmology · Physics 2019-03-29 Pisin Chen , Hsiao-Heng Yeh , Dong-han Yeom

We investigate the dynamics of single and multiple scalar fields with exponential potentials, leading to power-law and assisted inflation, in loop quantum cosmology. Unlike in the classical theory, dynamical trajectories in loop quantum…

General Relativity and Quantum Cosmology · Physics 2012-07-05 Evan Ranken , Parampreet Singh

In this article, I mainly discuss the dynamics of the pre-inflationary Universe for the potential $V(\phi) \propto \phi^n$ with $n=5/3$ in the context of loop quantum cosmology, in which the big bang singularity is resolved by a…

General Relativity and Quantum Cosmology · Physics 2018-08-14 M. Shahalam

In this study, we explore the pre-inflationary dynamics of the universe using a noncommutative extension of the mLQC-I framework. By incorporating a scalar field potential, we show that key features of Loop Quantum Cosmology (LQC), such as…

General Relativity and Quantum Cosmology · Physics 2024-08-13 Abolhassan Mohammadi

In this paper we study slow-roll inflation with holonomy corrections from loop quantum cosmology. Both tensor and scalar power spectra of primordial perturbations are computed up to the first order in slow-roll parameters and $V/\rho_{c}$,…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Jakub Mielczarek

We investigate the primordial power spectrum of cosmological tensor perturbations in the dressed metric approach to Loop Quantum Cosmology. We compute the background-dependent effective mass that affects their propagation using the…

General Relativity and Quantum Cosmology · Physics 2024-09-30 Ana Alonso-Serrano , Guillermo A. Mena Marugan , Antonio Vicente-Becerril

We investigate the role played by the vacuum of the primordial fluctuations in hybrid Loop Quantum Cosmology. We consider scenarios where the inflaton potential is a mass term and the unperturbed quantum geometry is governed by the…

General Relativity and Quantum Cosmology · Physics 2018-09-27 Beatriz Elizaga Navascués , Daniel Martín de Blas , Guillermo A. Mena Marugán

In Loop Quantum Cosmology, the quantization of the Hamiltonian constraint involves a regularization procedure which is affected by certain ambiguities. Moreover, different regularizations lead to distinct mathematical formulations and,…

General Relativity and Quantum Cosmology · Physics 2025-03-21 Maciej Kowalczyk , Guillermo A. Mena Marugán , Tomasz Pawłowski

We characterize in an analytical way the general conditions that a choice of vacuum state for the cosmological perturbations must satisfy to lead to a power spectrum with no scale-dependent oscillations over time. In particular, we pay…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Beatriz Elizaga Navascués , Guillermo A. Mena Marugán , Santiago Prado

In loop quantum cosmology (LQC) the big bang is replaced by a quantum bounce which is followed by a robust phase of super-inflation. Rather than growing unboundedly in the past, the Hubble parameter \emph{vanishes} at the bounce and attains…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Abhay Ashtekar , David Sloan

We provide the power spectrum of small scalar perturbations propagating in an inflationary scenario within loop quantum cosmology. We consider the hybrid quantization approach applied to a Friedmann--Robertson--Walker spacetime with flat…

General Relativity and Quantum Cosmology · Physics 2016-06-22 Daniel Martín de Blas , Javier Olmedo

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
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