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Related papers: Towards a reduced phase space quantization in loop…

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Quantum reduced loop gravity is designed to consistently study symmetry reduced systems within the loop quantum gravity framework. In particular, it bridges the gap between the effective cosmological models of loop quantum cosmology and the…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Emanuele Alesci , Aurélien Barrau , Gioele Botta , Killian Martineau , Gabriele Stagno

This work studies the quantum cosmology of a closed, spatially homogeneous, and isotropic FLRW minisuperspace model with electromagnetic radiation as a matter content. We solve the associated Wheeler-DeWitt (WDW) equation using the…

General Relativity and Quantum Cosmology · Physics 2023-04-20 S. Jalalzadeh , A. Mohammadi , D. Demir

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 consider the semi-classical dynamics of a free massive scalar field in a homogeneous and isotropic cosmological spacetime. The scalar field is quantized using the polymer quantization method assuming that it is described by a gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-11 Syed Moeez Hassan , Viqar Husain , Sanjeev S. Seahra

Precise cosmological data from WMAP and forthcoming CMB experiments motivate the study of the quantum corrections to the slowroll inflationary parameters.We find the quantum (loop) corrections to the equations of motion of the classical…

Astrophysics · Physics 2009-11-10 D. Boyanovsky , H. J. de Vega , N. G. Sanchez

In this work, a flat Friedmann-Robertson-Walker (FRW) universe with dust and a cosmological constant is quantized. By means of a canonical transformation, the classical Hamiltonian is reduced to that of either a harmonic oscillator or…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Edésio M. Barboza , Nivaldo A. Lemos

In this paper we study dynamics of the closed FRW model with holonomy corrections coming from loop quantum cosmology. We consider models with a scalar field and cosmological constant. In case of the models with cosmological constant and…

General Relativity and Quantum Cosmology · Physics 2009-11-19 Jakub Mielczarek , Orest Hrycyna , Marek Szydlowski

The primordial Universe can be used as a laboratory to set constraints on quantum gravity. In the framework of Loop Quantum Cosmology, we show that such a proposal for quantum gravity not only solves for the big bang singularity issue but…

General Relativity and Quantum Cosmology · Physics 2012-06-08 Julien Grain

This paper studies the reduced phase space formulation (relational formalism) of gravity coupling to the Brown-Kucha\v r dust for asymptotic flat spacetimes. A set of boundary conditions for the asymptotic flatness are formulated for Dirac…

General Relativity and Quantum Cosmology · Physics 2023-09-08 Muxin Han , Zichang Huang , Hongwei Tan

In this paper we consider realistic model of inflation embedded in the framework of loop quantum cosmology. Phase of inflation is preceded here by the phase of a quantum bounce. We show how parameters of inflation depend on the initial…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Jakub Mielczarek

Inflation is a necessary cosmic mechanism to cure basic inconsistencies of the standard model of cosmology. These problems are usually `fixed' by postulating the existence of a scalar field (called the ``inflaton''). However, other less ad…

General Relativity and Quantum Cosmology · Physics 2026-01-16 Joan Solà Peracaula , Àlex González-Fuentes , Cristian Moreno-Pulido

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

Phenomenological effect of the super-inflation in loop quantum cosmology (LQC) is discussed. We investigate the case that the Universe is filled with the interacting field between massive scalar field and radiation. Considering the damping…

General Relativity and Quantum Cosmology · Physics 2013-11-28 Kui Xiao , Xiao-Kai He , Jian-Yang Zhu

We generalise Starobinsky's model of inflation to space-times with $D>4$ dimensions, where $D-4$ dimensions are compactified on a suitable manifold. The $D$-dimensional action features Einstein-Hilbert gravity, a higher-order curvature…

High Energy Physics - Theory · Physics 2017-02-28 Santiago Pajón Otero , Francisco G. Pedro , Clemens Wieck

In the context of loop quantum cosmology, we consider an inflationary era driven by a canonical scalar field and occurring in the semiclassical regime, where spacetime is a continuum but quantum gravitational effects are important. The…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Gianluca Calcagni , Marina Cortes

We perform a phase space analysis of a non-minimally coupled modified gravity theory with the Lagrangian density of the form $\frac{1}{2} f_{1}(R)+[1+\lambda f_{2}(R)]{{\cal{L}}_{m}}$, where $f_1(R)$ and $f_2(R)$ are arbitrary functions of…

General Relativity and Quantum Cosmology · Physics 2014-06-03 Tahereh Azizi , Emad Yaraie

In loop quantum cosmology, the universe avoids a big bang singularity and undergoes an early and short super-inflation phase. During super-inflation, non-perturbative quantum corrections to the dynamics drive an inflaton field up its…

Astrophysics · Physics 2011-02-23 Shinji Tsujikawa , Parampreet Singh , Roy Maartens

Loop quantum cosmology is a symmetry-reduced application of loop quantum gravity. The theory predicts a bounce for the universe at the Planck scale and resolves the singularity of standard cosmology. The dynamics is also governed by an…

General Relativity and Quantum Cosmology · Physics 2024-06-27 Abolhassan Mohammadi

We study a new approach to generally covariant quantum mechanics applied in the case of an FLRW cosmological background. For positive spatial curvature we find a discrete series of solutions of the Klein-Gordon equation that can reasonably…

General Relativity and Quantum Cosmology · Physics 2025-11-13 Edwin Beggs , Shahn Majid

We investigate observational constraints on inflationary parameters in the context of an holographic cosmology with an induced gravity correction. We consider two situations where a universe is firstly filled with a scalar field and…

High Energy Physics - Theory · Physics 2020-04-21 Aatifa Bargach , Farida Bargach , Ahmed Errahmani , Taoufik Ouali
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