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Related papers: Probability of Inflation in Loop Quantum Cosmology

200 papers

It has been widely claimed that inflation is generically eternal to the future, even in models where the inflaton potential monotonically increases away from its minimum. The idea is that quantum fluctuations allow the field to jump uphill,…

High Energy Physics - Theory · Physics 2009-11-11 Steven Gratton , Neil Turok

Loop Quantum Gravity (L.Q.G.) is one of the two most promising tentative theory for a quantum description of gravity. When applied to the entire universe, the so-called Loop Quantum Cosmology (L.Q.C.) framework offers microscopical models…

General Relativity and Quantum Cosmology · Physics 2014-11-20 J. Grain

Quantum gravity, as a fundamental theory of space-time, is expected to reveal how the universe may have started, perhaps during or before an inflationary epoch. It may then leave a potentially observable (but probably minuscule) trace in…

General Relativity and Quantum Cosmology · Physics 2015-12-17 Martin Bojowald

The inflationary and pre-inflationary evolution of scalar modes of cosmological perturbations in a closed universe is analyzed for a loop quantum cosmology model with an inflationary regime consistent with the constraints on inflation…

General Relativity and Quantum Cosmology · Physics 2024-11-26 Lucas M. V. Montese , Nelson Yokomizo

We find the best-fit cosmological parameters for a scenario of inflation with only the sufficient amount of accelerated expansion for the $\lambda\phi^4$ potential. While for the simplest scenario of chaotic inflation all observable…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-25 Erandy Ramirez , Dominik J. Schwarz

Making observable predictions for cosmic inflation requires determining when the wavenumbers of astrophysical interest today exited the Hubble radius during the inflationary epoch. These instants are commonly evaluated using the slow-roll…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-17 Pierre Auclair , Baptiste Blachier , Christophe Ringeval

Usual inflation is realized with a slow rolling scalar field minimally coupled to gravity. In contrast, we consider dynamics of a scalar with a flat effective potential, conformally coupled to gravity. Surprisingly, it contains an attractor…

High Energy Physics - Theory · Physics 2008-11-26 Lev Kofman , Shinji Mukohyama

Space-based missions studying the cosmic microwave background (CMB) have progressively refined the parameter space in conventional models of inflation shortly ($\sim 10^{-37}$ seconds) after the big bang. While most inflationary scenarios…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-18 Jingwei Liu , Fulvio Melia

Recent cosmic microwave background observations favor low energy scale inflationary models in a closed universe. However, onset of inflation in such models for a closed universe is known to be severely problematic. In particular, such a…

General Relativity and Quantum Cosmology · Physics 2021-03-03 Lucia Gordon , Bao-Fei Li , Parampreet Singh

Inflation is part of the Standard Model of the Universe supported by CMB and large scale structure LSS datasets. This review presents new developments of inflation in three main chapters. (I): The effective theory of inflation a la…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-13 D. Boyanovsky , C. Destri , H. J. de Vega , N. G. Sanchez

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

We investigate the quantum cosmological tunneling scenario for inflationary models. Within a path-integral approach, we derive the corresponding tunneling probability distribution. A sharp peak in this distribution can be interpreted as the…

General Relativity and Quantum Cosmology · Physics 2014-10-15 Gianluca Calcagni , Claus Kiefer , Christian F. Steinwachs

Qualitative dynamics of three different loop quantizations of spatially flat isotropic and homogeneous models is studied using effective spacetime description of the underlying quantum geometry. These include the standard loop quantum…

General Relativity and Quantum Cosmology · Physics 2018-10-03 Bao-Fei Li , Parampreet Singh , Anzhong Wang

We propose a method to extract predictions from quantum cosmology for inflation that can be confronted with observations. Employing the tunneling boundary condition in quantum geometrodynamics, we derive a probability distribution for the…

General Relativity and Quantum Cosmology · Physics 2015-07-21 Gianluca Calcagni , Claus Kiefer , Christian F. Steinwachs

The era of precision cosmology has allowed us to accurately determine many important cosmological parameters, in particular via the CMB. Confronting Loop Quantum Cosmology with these observations provides us with a powerful test of the…

General Relativity and Quantum Cosmology · Physics 2012-04-06 Ivan Agullo , Abhay Ashtekar , William Nelson

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

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

Inflation has been the driving idea in cosmology for two decades and is a pillar of the New Cosmology. The inflationary paradigm has now passed its first round of significant tests, with two of its three basics predictions confirmed at…

Astrophysics · Physics 2014-10-13 Michael S. Turner

Inflation creates large-scale cosmological density perturbations that are characterized by an isotropic, homogeneous, and Gaussian random distribution about a locally flat background. Even in a flat universe, the spatial curvature measured…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Matthew Kleban , Marjorie Schillo

This article addresses the issue of estimating the duration in inflation in bouncing cosmology when anisotropies, inevitably playing an important role, are taken into account. It is shown that in Bianchi-I loop quantum cosmology, the higher…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Linda Linsefors , Aurelien Barrau