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Related papers: Inflationary scalar spectrum in loop quantum cosmo…

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We suggest a new conceptual frame where inflationary Cosmology is quantum mechanically described using the Hilbert space representation of the crossed product of the type $III$ factor associated with the algebra of local operators on the de…

High Energy Physics - Theory · Physics 2022-07-15 Cesar Gomez

We treat a model in which tensor perturbations of de~Sitter spacetime, represented as a spatially flat model, are modified by the effects of the vacuum fluctuations of a massless conformally invariant field, such as the electromagnetic…

General Relativity and Quantum Cosmology · Physics 2011-05-05 Jen-Tsung Hsiang , L. H. Ford , Da-Shin Lee , Hoi-Lai Yu

The (large-scale) structures we observe in the Universe are classical, but within the inflationary scenario they do originate from quantum fluctuations. This leads to the question: ''How did this quantum-to-classical transition occur?''. A…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-19 Jessie de Kruijf , Giacomo Galloni , Nicola Bartolo

We propose a new class of inflationary models in which the scalar field potential governing inflation is generated by the same non-perturbative gauge dynamics that may lead to supersymmetry breaking. Such models satisfy constraints from…

High Energy Physics - Phenomenology · Physics 2011-05-23 William H. Kinney , Antonio Riotto

We propose a class of scalar models that, once coupled to gravity, lead to cosmologies that smoothly and stably connect an inflationary quasi-de Sitter universe to a low, or even zero-curvature, maximally symmetric spacetime in the…

High Energy Physics - Theory · Physics 2015-06-23 David Pirtskhalava , Luca Santoni , Enrico Trincherini , Patipan Uttayarat

Motivated by the gauge theory of gravity with local scaling symmetry proposed recently in 1712.04537 and 1506.01807, we investigate whether the scalar field therein can be responsible for the inflation. We show that the classical theory…

General Relativity and Quantum Cosmology · Physics 2018-08-07 Yong Tang , Yue-Liang Wu

The representation theory of de Sitter space allows for a category of partially massless particles which have no flat space analog, but could have existed during inflation. We study the couplings of these exotic particles to inflationary…

High Energy Physics - Theory · Physics 2018-05-23 Daniel Baumann , Garrett Goon , Hayden Lee , Guilherme L. Pimentel

Numerical simulations of the inflationary dynamics are presented here for a single canonical scalar field minimally coupled to gravity. We spell out the basic equations governing the inflationary dynamics in terms of cosmic time $t$ and…

General Relativity and Quantum Cosmology · Physics 2024-08-29 Siddharth S. Bhatt , Swagat S. Mishra , Soumen Basak , Surya N. Sahoo

In this work, we investigate inflationary cosmology using scalar field theory deformed by the generalized uncertainty principle (GUP) containing a linear momentum term. Apart from being consistent with the existence of a minimum measurable…

General Relativity and Quantum Cosmology · Physics 2015-12-02 Ahmed Farag Ali , Mir Faizal , Mohammed M. Khalil

We consider inflation with a constant rate of rolling in which a complex scalar field plays the role of inflaton during the inflationary epoch. We implement the inflationary analysis for an accredited angular speed $\dot{\theta}$ which…

General Relativity and Quantum Cosmology · Physics 2024-05-16 Ramón Herrera , Mehdi Shokri , Jafar Sadeghi

In the inflationary scenario of loop quantum cosmology in the presence of inverse-volume corrections, we give analytic formulas for the power spectra of scalar and tensor perturbations convenient to compare with observations. Since…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 Martin Bojowald , Gianluca Calcagni , Shinji Tsujikawa

Inflationary cosmology proposes that the early Universe undergoes accelerated expansion, driven, in simple scenarios, by a single scalar field, or inflaton. The form of the inflaton potential determines the initial spectra of density…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 Richard Easther , Benedict Bahr-Kalus , David Parkinson

We derive the primordial power spectrum of density fluctuations in the framework of quantum cosmology. For this purpose we perform a Born-Oppenheimer approximation to the Wheeler-DeWitt equation for an inflationary universe with a scalar…

General Relativity and Quantum Cosmology · Physics 2012-01-17 Claus Kiefer , Manuel Kraemer

We exploit a previous computation of the self-mass-squared from quantum gravity to include quantum corrections to the scalar evolution equation. The plane wave mode functions are shown to receive no significant one loop corrections at late…

General Relativity and Quantum Cosmology · Physics 2008-11-26 E. O. Kahya , R. P. Woodard

We quantize to completion an inflationary universe with small inhomogeneities in the framework of loop quantum cosmology. The homogeneous setting consists of a massive scalar field propagating in a closed, homogeneous scenario. We provide a…

General Relativity and Quantum Cosmology · Physics 2012-07-20 Mikel Fernández-Méndez , Guillermo A. Mena Marugán , Javier Olmedo

We study the evolution of quantum fluctuations of a scalar field which is coupled to the geometry, in an exponentially expanding universe. We derive an expression for the spectrum of intrinsic perturbations, and it is shown that the…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Jelle Boersma

In this paper we revisit and extend a previous analysis where the possible relevance of quantum gravity effects in a cosmological setup was studied. The object of interest are non-local (logarithmic) terms generated in the effective action…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. A. Cabrer , D. Espriu

In this paper we discuss the inflationary universe in the context of a Chaplygin gas equation of state within the framework of the effective theory of loop quantum cosmology. Under the slow-roll approximation, we calculate the primordial…

General Relativity and Quantum Cosmology · Physics 2009-08-20 Xin Zhang , Jingfei Zhang , Jinglei Cui , Li Zhang

A brief review of the modern state of quantum cosmology is presented as a theory of quantum initial conditions for inflationary scenario. The no-boundary and tunneling states of the Universe are discussed as a possible source of probability…

General Relativity and Quantum Cosmology · Physics 2017-08-23 A. O. Barvinsky

We derive the semiclassical evolution of massless minimally coupled scalar matter in the de Sitter space-time from the Born-Oppenheimer reduction of the Wheeler-DeWitt equation. We show that the dynamics of trans-Planckian modes can be cast…

High Energy Physics - Theory · Physics 2009-11-11 Gian Luigi Alberghi , Roberto Casadio , Alessandro Tronconi