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Related papers: Perturbations in loop quantum cosmology

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Loop quantum cosmology is an application of recent developments for a non-perturbative and background independent quantization of gravity to a cosmological setting. Characteristic properties of the quantization such as discreteness of…

Astrophysics · Physics 2009-11-13 Martin Bojowald

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

The probability of there being sufficient inflation to solve the fine-tuning associated with the horizon and flatness problems has recently been shown to be exponentially small, within the context of classical general relativity. Here this…

General Relativity and Quantum Cosmology · Physics 2007-08-27 William Nelson

The cosmological primordial power spectrum is known to be one of the most promising observable to probe quantum gravity effects. In this article, we investigate how the tensor power spectrum is modified by Loop Quantum Gravity corrections.…

General Relativity and Quantum Cosmology · Physics 2010-04-06 J. Grain , T. Cailleteau , A. Barrau , A. Gorecki

Following the pioneering observations with COBE in the early 1990s, studies of the cosmic microwave background (CMB) have focused on temperature and polarization anisotropies. CMB spectral distortions - tiny departures of the CMB energy…

Understanding the behavior of the universe at large depends critically on insights about the smallest units of matter and their fundamental interactions. Inflationary cosmology is a highly successful framework for exploring these…

Astrophysics · Physics 2009-11-10 Alan H. Guth , David I. Kaiser

The difficult issues related to the interpretation of quantum mechanics and, in particular, the "measurement problem" are revisited using as motivation the process of generation of structure from quantum fluctuations in inflationary…

General Relativity and Quantum Cosmology · Physics 2014-12-25 Mario Castagnino , Sebastian Fortin , Roberto Laura , Daniel Sudarsky

The conventional $\Lambda$CDM cosmological model supplemented by the inflation concept describes the Universe very well. However, there are still a few concerns: new Planck data impose constraints on the shape of the inflaton potential,…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-03 Branislav Vlahovic , Maxim Eingorn , Cosmin Ilie

Within a perturbative cosmological regime of loop quantum gravity corrections to effective constraints are computed. This takes into account all inhomogeneous degrees of freedom relevant for scalar metric modes around flat space and results…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald , Hector Hernandez , Mikhail Kagan , Aureliano Skirzewski

The Universe is the grandest conceivable scale on which the human mind can strive to understand nature. The amazing aspect of cosmology, the branch of science that attempts to understand the origin and evolution of the Universe, is that it…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-19 Tarun Souradeep

We derive the primordial power spectra and spectral indexes of the density fluctuations and gravitational waves in the framework of loop quantum cosmology (LQC) with holonomy and inverse-volume corrections, by using the uniform asymptotic…

General Relativity and Quantum Cosmology · Physics 2015-08-04 Tao Zhu , Anzhong Wang , Gerald Cleaver , Klaus Kirsten , Qin Sheng , Qiang Wu

We consider the description of cosmological dynamics from the onset of inflation by a perfect fluid whose parameters must be consistent with the strength of the enhanced quantum loop effects that can arise during inflation. The source of…

General Relativity and Quantum Cosmology · Physics 2010-04-14 N. C. Tsamis , R. P. Woodard

Cosmic inflation is commonly assumed to be driven by quantum fields. Quantum mechanics predicts phenomena such as quantum fluctuations and tunneling of the field. Here we show an example of a quantum interference effect which goes beyond…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-01 Igor Pikovski , Abraham Loeb

This is the dawning of the age of precision cosmology, when all the important parameters will be established to one significant figure or better, within the cosmological model. In the age of accurate cosmology the model, which nowadays…

Astrophysics · Physics 2007-05-23 P. J. E. Peebles

Power spectra always play an important role in the theory of inflation. In particular, the ability to reproduce the galaxy matter power spectrum and the CMB temperature angular power spectrum coefficients to high accuracy is often…

General Relativity and Quantum Cosmology · Physics 2019-11-01 Herbert W. Hamber , Lu Heng Sunny Yu

After introducing the basic ingredients of Loop Quantum Cosmology, I will briefly discuss some of its phenomenological aspects. Those can give some useful insight about the full Loop Quantum Gravity theory and provide an answer to some…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Mairi Sakellariadou

Quantum mechanical metric fluctuations during an early inflationary phase of the universe leave a characteristic imprint in the polarization of the cosmic microwave background (CMB). The amplitude of this signal depends on the energy scale…

Quantum effects are expected to modify the cosmological dynamics of the early universe while maintaining some (potentially discrete) notion of space-time structure. In one approach, loop quantum cosmology, current models are shown here to…

General Relativity and Quantum Cosmology · Physics 2026-04-29 Martin Bojowald , Manuel Diaz , Erick I. Duque

Observational cosmology is in its "golden age" with a vast amount of recent data on the distribution of matter and light in the universe. This data can be used to probe theories of the very early universe. It is small amplitude cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Robert H. Brandenberger

Loop Quantum Gravity is a nonperturbative and background independent program for the quantization of General Relativity. Its underlying formalism has been applied successfully to the study of cosmological spacetimes, both to test the…

General Relativity and Quantum Cosmology · Physics 2021-09-13 Beatriz Elizaga Navascués , Guillermo A. Mena Marugán
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