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Related papers: Holographic Non-Gaussianity

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We investigate the non-Gaussianity of primordial cosmological perturbations using holographic methods. In particular, we derive holographic formulae that relate all cosmological 3-point correlation functions, including both scalar and…

High Energy Physics - Theory · Physics 2011-07-01 Paul McFadden , Kostas Skenderis

We present a holographic description of four-dimensional single-scalar inflationary universes in terms of a three-dimensional quantum field theory. The holographic description correctly reproduces standard inflationary predictions in their…

High Energy Physics - Theory · Physics 2010-06-11 Paul McFadden , Kostas Skenderis

We discuss the phenomenology of recently proposed holographic models of inflation, in which the very early universe is non-geometric and is described by a dual three-dimensional quantum field theory (QFT). We analyze models determined by a…

High Energy Physics - Theory · Physics 2016-11-15 Paul McFadden , Kostas Skenderis

In this review, we discuss how non-Gaussianity of cosmological perturbations arises from inflation. After introducing the in-in formalism to calculate the $n$-point correlation function of quantum fields, we present the computation of the…

High Energy Physics - Theory · Physics 2014-11-20 Kazuya Koyama

We use holographic techniques to compute inflationary non-Gaussianities for general single-field inflation, including models with a non-trivial sound speed. In this holographic approach, the inflationary dynamics is captured by a relevant…

High Energy Physics - Theory · Physics 2016-12-14 Hiroshi Isono , Toshifumi Noumi , Gary Shiu , Sam S. C. Wong , Siyi Zhou

Holographic cosmology offers a novel framework for describing the very early Universe in which cosmological predictions are expressed in terms of the observables of a three dimensional quantum field theory (QFT). This framework includes…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-14 Niayesh Afshordi , Elizabeth Gould , Kostas Skenderis

We propose a holographic description of four-dimensional single-scalar inflationary universes, and show how cosmological observables, such as the primordial power spectrum, are encoded in the correlation functions of a three-dimensional…

High Energy Physics - Theory · Physics 2010-05-19 Paul McFadden , Kostas Skenderis

We present the holographic predictions for cosmological 3-point correlators, involving both scalar and tensor modes, for a universe which started in a non-geometric holographic phase. Holographic formulae relate the cosmological 3-point…

High Energy Physics - Theory · Physics 2012-04-11 Adam Bzowski , Paul McFadden , Kostas Skenderis

We investigate thermal inflation in double-screen entropic cosmology. We find that its realization is general, resulting from the system evolution from non-equilibrium to equilibrium. Furthermore, going beyond the background evolution, we…

High Energy Physics - Theory · Physics 2011-05-26 Yi-Fu Cai , Emmanuel N. Saridakis

We extend the \delta N formalism so that it gives all of the stochastic properties of the primordial curvature perturbation \zeta if the initial field perturbations are gaussian. The calculation requires only the knowledge of some family of…

Astrophysics · Physics 2011-06-08 David H. Lyth , Yeinzon Rodriguez

Cosmic inflation may have led to non-Gaussian initial conditions that cannot be fully parametrised by 3- and/or 4-point functions. In this work, we discuss various strategies to search for primordial non-Gaussianity beyond polyspectra with…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-03 Gonzalo A. Palma , Bruno Scheihing Hitschfeld , Spyros Sypsas

The late-time effect of primordial non-Gaussianity offers a window into the physics of inflation and the very early Universe. In this work we study the consequences of a particular class of primordial non-Gaussianity that is fully…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 G. A. Peña , G. N. Candlish

We derive a formula for the halo/galaxy bispectrum on the basis of the integrated Perturbation Theory (iPT). In addition to the gravity-induced non-Gaussianity, we consider the non-Gaussianity of the primordial curvature perturbations, and…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-07 Shuichiro Yokoyama , Takahiko Matsubara , Atsushi Taruya

The non-Gaussianity of inflationary perturbations, as encoded in the bispectrum (or 3-point correlator), has become an important additional way of distinguishing between inflation models, going beyond the linear Gaussian perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-23 Bartjan van Tent

If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Sander Mooij , Gonzalo A. Palma , Grigoris Panotopoulos , Alex Soto

We calculate the three-point correlation function evaluated at horizon crossing for a set of interacting scalar fields coupled to gravity during inflation. This provides the initial condition for the three-point function of the curvature…

Astrophysics · Physics 2008-11-26 David Seery , James E. Lidsey

We discuss how primordial non-Gaussianity of the curvature perturbation helps to constrain models of the early universe. Observations are consistent with Gaussian initial conditions, compatible with the predictions of the simplest models of…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-26 Christian T. Byrnes

After a brief review of the different approaches to predict the possible quantum gravity corrections to quantum field theory, we discuss in some detail the formulation based on a Gaussian reference frame fixing. Then, we implement this…

General Relativity and Quantum Cosmology · Physics 2023-06-12 Giulia Maniccia , Giovanni Montani , Leonardo Torcellini

We investigate non-Gaussianity in general multiple-field inflation using the formalism we developed in earlier papers. We use a perturbative expansion of the non-linear equations to calculate the three-point correlator of the curvature…

Astrophysics · Physics 2009-11-13 G. I. Rigopoulos , E. P. S. Shellard , B. J. W. van Tent

We compute analytic expressions for the non-linearity parameters characterizing the bi- and tri-spectrum of primordial curvature perturbations generated during an inflationary epoch of the early universe driven by an arbitrary number of…

High Energy Physics - Theory · Physics 2011-11-04 Diana Battefeld , Thorsten Battefeld
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