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Studying the primordial non-Gaussianity of inflationary perturbations is crucial for testing the inflation paradigm of the early universe. In this work, we conduct a comprehensive analysis of the angular bispectrum and trispectrum of…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-30 Jun-Peng Li , Sai Wang , Zhi-Chao Zhao , Kazunori Kohri

There is growing interest in quantum-spacetime models in which small departures from Lorentz symmetry are governed by the Planck scale. In particular, several studies have considered the possibility that these small violations of Lorentz…

High Energy Physics - Phenomenology · Physics 2009-11-10 Giovanni Amelino-Camelia , Michele Arzano , Y. Jack NG , Tsvi Piran , Hendrik Van Dam

We present projections for reconstruction of the inflationary potential expected from ESA's upcoming Planck Surveyor CMB mission. We focus on the effects that tensor perturbations and the presence of non-Gaussianities have on reconstruction…

Astrophysics · Physics 2009-11-13 Brian A. Powell , Konstantinos Tzirakis , William H. Kinney

We apply the time-renormalization group approach to study the effect of primordial non-Gaussianities in the non-linear evolution of cosmological dark matter density perturbations. This method improves the standard perturbation approach by…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Nicola Bartolo , J. P. Beltran Almeida , Sabino Matarrese , Massimo Pietroni , Antonio Riotto

We present an all-sky formalism for the Cosmic Microwave Background (CMB) bispectrum induced by the primordial non-Gaussianities not only in scalar but also in vector and tensor fluctuations. We find that the bispectrum can be formed in an…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki , Keitaro Takahashi

With the advent of galaxy surveys which provide large samples of galaxies or galaxy clusters over a volume comparable to the horizon size (SDSS-III, HETDEX, Euclid, JDEM, LSST, Pan-STARRS, CIP etc.) or mass-selected large cluster samples…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Licia Verde

Analytic expressions for the statistics of peaks of random fields with weak non-Gaussianity are provided. Specifically, the abundance and spatial correlation of peaks are represented by formulas which can be evaluated only by virtually…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-04 Takahiko Matsubara

We outline the expected constraints on non-Gaussianity from the cosmic microwave background (CMB) with current and future experiments, focusing on both the third (f_{NL}) and fourth-order (g_{NL} and \tau_{NL}) amplitudes of the local…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-27 Joseph Smidt , Alexandre Amblard , Christian T. Byrnes , Asantha Cooray , Alan Heavens , Dipak Munshi

We discuss models of primordial density perturbations where the non-Gaussianity is strongly scale-dependent. In particular, the non-Gaussianity may have a sharp cut-off and be very suppressed on large cosmological scales, but sizeable on…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-18 Antonio Riotto , Martin S. Sloth

Non-Gaussianity in the primordial fluctuations that seeded structure formation produces a signal in the galaxy power spectrum on very large scales. This signal contains vital information about the primordial Universe, but it is very…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Stefano Camera , Roy Maartens , Mario G. Santos

We numerically integrate the Einstein's equations for a spatially flat Friedmann-Lemaire-Robertson-Walker (FLRW) background spacetime with a spatial curvature perturbation and evolving primordial tensor perturbations using the Einstein…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-29 Ke Wang

We approximately compute the bispectrum induced on the CMB temperature by fluctuations in the standard recombination epoch. Of all the second order sources that can induce non-Gaussianity during recombination, we concentrate on those…

Astrophysics · Physics 2009-10-02 Leonardo Senatore , Svetlin Tassev , Matias Zaldarriaga

It is possible to classify pixels of a smoothed cosmic microwave background (CMB) fluctuation map according to their local curvature in ``hill'', ``lake'' and ``saddle'' regions. In the Gaussian case, fractional areas occupied by pixels of…

Astrophysics · Physics 2011-05-10 O. Doré , S. Colombi , F. R. Bouchet

We present estimates of the response to polarized signals by the PLANCK telescope. These estimates are based on a set of simulations, using a physical optics code (GRASP8), for linearly polarized detectors at different frequencies and…

Astrophysics · Physics 2009-11-07 G. Franco , P. Fosalba , J. A. Tauber

We study a particular Galileon inflation in the light of Planck2015 observational data in order to constraint the model parameter space. We study the spectrum of the primordial modes of the density perturbations by expanding the action up…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Kosar Asadi , Kourosh Nozari

Next-generation galaxy and 21cm intensity mapping surveys will rely on a combination of the power spectrum and bispectrum for high-precision measurements of primordial non-Gaussianity. In turn, these measurements will allow us to…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-08 Roy Maartens , Sheean Jolicoeur , Obinna Umeh , Eline M. De Weerd , Chris Clarkson

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

We consider gravitational clustering from primoridal non-Gaussian fluctuations provided by a $\chi^2$ model, as motivated by some models of inflation. The emphasis is in signatures that can be used to constrain this type of models from…

Astrophysics · Physics 2009-10-31 Roman Scoccimarro

This talk briefly explains how the breaking of a Lorentz-invariant description of nature at tiny space-time intervals might affect the non-Gaussian character of the primordial fluctuations left by inflation. For example, a model that…

High Energy Physics - Theory · Physics 2014-11-20 Hael Collins

A generalized theory of multi-field galileons has been recently put forward. This model stems from the ongoing effort to embed generic galileon theories within brane constructions. Such an approach has proved very useful in connecting…

High Energy Physics - Theory · Physics 2015-06-15 Matteo Fasiello