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Related papers: Inflationary Perturbations from Deformed CFT

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Probing correlations among short and long-wavelength cosmological fluctuations is known to be decisive for deepening the current understanding of inflation at the microphysical level. Spectral distortions of the CMB can be caused by…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Emanuela Dimastrogiovanni , Razieh Emami

A pressing problem in comparing inflationary models with observation is the accurate calculation of correlation functions. One approach is to evolve them using ordinary differential equations ("transport equations"), analogous to the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-10 David Seery , David J. Mulryne , Jonathan Frazer , Raquel H. Ribeiro

We consider the Einstein equations within the DBI scenario for a spatially flat Friedmann-Robertson-Walker (FRW) spacetime without a cosmological constant. We derive the inflationary scenario by applying the symmetry transformations which…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 L. P. Chimento , R. Lazkoz , M. G. Richarte

The usual description of inflationary fluctuations uses the framework of quantum field theory (QFT) in curved spacetime, in which quantum fluctuations are superimposed on a classical background spacetime. Even for large fluctuations, such…

General Relativity and Quantum Cosmology · Physics 2020-03-11 Sebastian F. Bramberger , Alice Di Tucci , Jean-Luc Lehners

We extend the WKB method for the computation of cosmological perturbations during inflation beyond leading order and provide the power spectra of scalar and tensor perturbations to second order in the slow-roll parameters. Our method does…

General Relativity and Quantum Cosmology · Physics 2009-11-11 R. Casadio , F. Finelli , M. Luzzi , G. Venturi

In previous work, we developed a method for computing two-point correlators by decomposing the mode degrees of freedom into fast and slow components. Building on this framework, we present a numerical implementation to study the evolution…

General Relativity and Quantum Cosmology · Physics 2026-03-04 Johor D. Peñalba Quispitupa , Guillermo F. Quispe Peña , Jose T. Galvez Ghersi

A disformal coupling between two scalar fields is considered in the context of cosmological inflation. The coupling introduces novel derivative interactions mixing the kinetic terms of the fields but without introducing superluminal or…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-23 Carsten van de Bruck , Tomi Koivisto , Chris Longden

The inflationary paradigm is the most successful model that explains the observed spectrum of primordial perturbations. However, the precise emergence of such inhomogeneities and the quantum-to-classical transition of the perturbations has…

General Relativity and Quantum Cosmology · Physics 2016-01-26 Gabriel Leon , Gabriel R. Bengochea

We initiate the study of multi-field inflation using holography. Bulk light scalar fields correspond to nearly marginal operators in the boundary theory and the dual quantum field theory is a deformation of a CFT by such operators. We…

High Energy Physics - Theory · Physics 2015-06-23 Jaume Garriga , Kostas Skenderis , Yuko Urakawa

We numerically calculate the evolution of second order cosmological perturbations for an inflationary scalar field without resorting to the slow-roll approximation or assuming large scales. In contrast to previous approaches we therefore…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-15 Ian Huston , Karim A. Malik

It has been pointed out that the perturbation spectrum predicted by inflation may be sensitive to a natural ultraviolet cutoff, thus potentially providing an experimentally accessible window to aspects of Planck scale physics. A priori, a…

Astrophysics · Physics 2009-11-06 A. Kempf , J. C. Niemeyer

In the present paper, we aim to generalize the constant-roll inflation in the non-canonical set-up, particularly in the context of scalar Dirac-Born-Infeld (DBI) theory which has emerged to be prospective candidate for describing inflation…

High Energy Physics - Theory · Physics 2018-07-05 Sayantani Lahiri

The meaning of the inflationary slow-roll approximation is formalised. Comparisons are made between an approach based on the Hamilton-Jacobi equations, governing the evolution of the Hubble parameter, and the usual scenario based on the…

Astrophysics · Physics 2009-10-22 Andrew R. Liddle , Paul Parsons , John D. Barrow

Holographic inflation posits that the inflationary deSitter era of our universe is approximately described by a dual three-dimensional Euclidean CFT living on the spatial slice at the end of inflation. We point out that the BICEP2 results…

High Energy Physics - Theory · Physics 2014-08-04 Finn Larsen , Andrew Strominger

Slow-roll inflation can be studied as an effective field theory. The form of the inflaton potential consistent with the data is V(phi) = N M^4 w(phi/[sqrt{N} M_{Pl}]) where phi is the inflaton field, M is the inflation energy scale, and N ~…

Astrophysics · Physics 2007-05-23 D. Boyanovsky , H. J. de Vega , N. G. Sanchez

We investigate the accuracy of the slow-roll approximation for calculating perturbation spectra generated during inflation. The Hamilton-Jacobi formalism is used to evolve inflationary models with different histories. Models are identified…

Astrophysics · Physics 2010-10-27 Sirichai Chongchitnan , George Efstathiou

We analyze how the spectrum of perturbations produced in a multi-component modular inflation model proposed by Kadota and Stewart depends on couplings between the two moduli. Although some simple direct couplings give essentially the same…

High Energy Physics - Phenomenology · Physics 2008-02-12 Wan-Il Park , Ewan D. Stewart

We obtain models of chaotic, slow--roll, hybrid and D--term inflation from the Hanany--Witten brane configuration and its deformations. The deformations are given by the different orientations of the branes and control the parameters of the…

High Energy Physics - Theory · Physics 2007-05-23 Edi Halyo

In this paper we study slow-roll inflation with holonomy corrections from loop quantum cosmology. Both tensor and scalar power spectra of primordial perturbations are computed up to the first order in slow-roll parameters and $V/\rho_{c}$,…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Jakub Mielczarek

By making a suitable generalization of the Starobinsky stochastic inflation, we propose a classical phase space formulation of stochastic inflation which may be used for a quantitative study of decoherence of cosmological perturbations…

General Relativity and Quantum Cosmology · Physics 2012-01-04 Jan Weenink , Tomislav Prokopec