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Related papers: Non-commutativity in modified loop cosmology

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Loop quantum cosmology of the closed isotropic model is studied with a special emphasis on a comparison with traditional results obtained in the Wheeler-DeWitt approach. This includes the relation of the dynamical initial conditions with…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Martin Bojowald , Kevin Vandersloot

Warm inflation is analyzed in the context of Loop Quantum Cosmology (LQC). The bounce in LQC provides a mean through which a Liouville measure can be defined, which has been used previously to characterize the a priori probability for…

General Relativity and Quantum Cosmology · Physics 2018-08-01 L. L. Graef , Rudnei O. Ramos

We study the cosmic evolution of an interacting scalar field radiation model, in which a minimally coupled scalar field exchanges energy with the radiation sector through an exponential coupling. Extending previous formulations, a…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-01 Dorian Araya , Felipe Herrera , Nelson Videla

An extremely fast exponential expansion of the Universe is typical for the stable version of the inflationary model, based on the anomaly-induced action of gravity. The total amount of exponential $e$-folds could be very large, before the…

High Energy Physics - Theory · Physics 2021-08-05 Wagno Cesar e Silva , Ilya L. Shapiro

The trans-Planckian censorship conjecture (TCC) puts an upper bound on the life-time of de Sitter spacetimes. It has immediate consequences for inflationary cosmology. In the standard paradigm, the universe has experienced a single stage of…

High Energy Physics - Theory · Physics 2020-03-18 Mahdi Torabian

We critically review the role of cosmological moduli in determining the post-inflationary history of the universe. Moduli are ubiquitous in string and M-theory constructions of beyond the Standard Model physics, where they parametrize the…

High Energy Physics - Theory · Physics 2015-08-06 Gordon Kane , Kuver Sinha , Scott Watson

In this work we shall explore the effects of non commutativity in fractional classical and quantum schemes using the flat Friedmmann-Robertson-Walker (FRW) cosmological model coupled to a scalar field in the K-essence formalism. In previous…

General Relativity and Quantum Cosmology · Physics 2024-03-04 J. Socorro , J. Juan Rosales , Leonel Toledo-Sesma

We consider the interacting holographic dark energy with new infrared cutoff (involving Hubble parameter and its derivative) in non-flat universe. In this context, we obtain the equation of state parameter which evolutes the universe from…

General Relativity and Quantum Cosmology · Physics 2015-06-12 M. Sharif , Abdul Jawad

Supergravity provides the natural supersymmetric framework for early universe cosmology. A broad class of inflationary models in no-scale supergravity yields tree-level predictions for cosmic microwave background (CMB) observables that…

High Energy Physics - Phenomenology · Physics 2026-03-04 John Ellis , Tony Gherghetta , Kunio Kaneta , Wenqi Ke , Keith A. Olive

We use the vacuum Bianchi I model as an example to investigate the concept of physical evolution in Loop Quantum Cosmology (LQC) in the absence of the massless scalar field which has been used so far in the literature as an internal time.…

General Relativity and Quantum Cosmology · Physics 2009-11-05 Mercedes Martin-Benito , Guillermo A. Mena Marugan , Tomasz Pawlowski

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

A semiclassical description of quantum systems is applied to probe the dynamics of the cosmological model of an inflationary universe with quadratic inflaton potential, described in a quantum framework of geometrodynamics. The systematic…

General Relativity and Quantum Cosmology · Physics 2022-10-27 David Brizuela , Tomasz Pawlowski

We study the modifications induced on scalar field inflation produced by considering a general modification of the Heisenberg algebra. We proceed by modifying the Poisson brackets on the classical theory whenever the corresponding quantum…

General Relativity and Quantum Cosmology · Physics 2024-08-13 H. Garcia-Compean , D. Mata-Pacheco

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

In this thesis, we discuss several instances in which non-linear behaviour affects cosmological evolution in the early Universe. We begin by reviewing the standard cosmological model and the tools used to understand it theoretically and to…

General Relativity and Quantum Cosmology · Physics 2019-11-20 Pedro Carrilho

In isotropic loop quantum cosmology, non-perturbatively modified dynamics of a minimally coupled scalar field violates weak, strong and dominant energy conditions when they are stated in terms of equation of state parameter. The violation…

General Relativity and Quantum Cosmology · Physics 2010-11-05 Golam Mortuza Hossain

Closed, singularity-free, inflationary cosmological models have recently been studied in the context of general relativity. Despite their appeal, these so called emergent models suffer from a number of limitations. These include the fact…

Astrophysics · Physics 2009-11-10 David J. Mulryne , Reza Tavakol , James E. Lidsey , George F. R. Ellis

The Hamilton-Jacobi approach is a powerful tool to describe super-Hubble dynamics during cosmological inflation in a non-linear way. A key assumption of this framework is to neglect anisotropic perturbations on large scales. We show that…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-15 Danilo Artigas , Emmanuel Frion , Tays Miranda , Vincent Vennin , David Wands

We calculate the time evolution of the expectation value of the energy-momentum tensor for a minimally-coupled massless scalar field in cosmological spacetimes, with an application to dark energy in mind. We first study the evolution from…

High Energy Physics - Theory · Physics 2014-06-11 Hajime Aoki , Satoshi Iso , Yasuhiro Sekino

For simple inflationary models, we provide a consistent and complete scheme by which the macro-physical details of early universe inflation may be determined explicitly from the underlying micro-physical theory. We examine inflationary…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Cormier