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Related papers: CMB Cold Spot from Inflationary Feature Scattering

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A systematic approach is presented for using CMB observables and reheating temperature for discriminating between various models of inflation and certain freeze-in dark matter scenarios. It is applied to several classes of…

High Energy Physics - Phenomenology · Physics 2025-11-26 Anish Ghoshal , Paweł Kozów , Marek Olechowski , Stefan Pokorski

We propose a new mechanism to generate density perturbations in inflationary models. Spatial fluctuations in the decay rate of the inflaton field to ordinary matter lead to fluctuations in the reheating temperature. We argue that in most…

Astrophysics · Physics 2009-11-07 Gia Dvali , Andrei Gruzinov , Matias Zaldarriaga

Future Cosmic Microwave Background (CMB) experiments will deliver extremely accurate measurements of the E-modes pattern of the CMB polarization field. Given the sharpness of the E-modes transfer functions, such surveys make for a powerful…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Matteo Braglia , Xingang Chen , Dhiraj Kumar Hazra , Lucas Pinol

We unify one of the most widely studied frameworks to explain the hierarchical structure of the flavor sector in the Standard Model, the Froggatt-Nielsen mechanism, with cosmic inflation. We propose that the complex scalar field, the…

High Energy Physics - Phenomenology · Physics 2026-02-26 Mu-Chun Chen , Anish Ghoshal , V. Knapp-Perez , Xueqi Li , Xiang-Gan Liu , Cameron Moffett-Smith

We forecast the detectability of the lensing footprint of a collapsing cosmic texture, a topological defect proposed as an explanation of the CMB Cold Spot. Our pipeline is a quadratic, template-amplitude estimator for localized,…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-08 Pedro da Silveira Ferreira , Stephen Owusu

The Wilkinson Microwave Anisotropy Probe microwave background data suggest that the primordial spectrum of scalar curvature fluctuations is suppressed at small wavenumbers. We propose a UV/IR mixing effect in small-field inflationary models…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. Buchel , F. A. Chishtie , V. Elias , Katherine Freese , R. B. Mann , D. G. C. McKeon , T. G. Steele

We present the status of our study into the feasibility of estimating the parameters of inflation from planned satellite observations of the anisotropy of the cosmic microwave background (CMB).We describe a perturbative procedure for…

[Abridged] A variety of model-dependent as well as model-independent approaches suggest that certain localized features in the primordial scalar power spectrum can lead to a significantly better fit to the observed anisotropies in the…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-16 Alipriyo Hoory , Dhiraj Kumar Hazra , L. Sriramkumar

We investigate the possibility that a heavy scalar field, whose mass exceeds the Hubble scale during inflation, could leave non-negligible signatures in the Cosmic Microwave Background (CMB) temperature anisotropy power spectrum through the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Ryo Saito , Masahiro Nakashima , Yu-ichi Takamizu , Jun'ichi Yokoyama

Within the context of supersymmetric hybrid inflation, we study a multiple-stage inflationary scenario that can generate a primordial spectrum of adiabatic density perturbations with a break at $k_b \simeq 0.05 h Mpc^{-1}$. The presence of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mairi Sakellariadou , Nikos Tetradis

We review the currrent cosmic parameter determinations of relevance to inflation using the WMAP-1year, Boomerang, CBI, Acbar and other CMB data. The basic steps in the pipelines which determine the bandpowers from the raw data from which…

Astrophysics · Physics 2009-11-10 J. R. Bond , C. R. Contaldi , A. M. Lewis , D. Pogosyan

We analyze an inflationary model in which part of the power in density perturbations arises due to particle production. The amount of particle production is modulated by an auxiliary field. Given an initial gradient for the auxiliary field,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Guido D'Amico , Roberto Gobbetti , Matthew Kleban , Marjorie Schillo

In a recent paper, we suggested that the density fluctuation spectra arising from power-law (or extended) inflation, which are tilted with respect to the Harrison--Zel'dovich spectrum, may provide an explanation for the excess large scale…

Astrophysics · Physics 2007-05-23 David H Lyth , Andrew A Liddle

In this article, we do a thorough investigation of the competency of the forthcoming Cosmic Microwave Background (CMB) and Galaxy surveys in probing the features in the primordial power spectrum. Primordial features are specific…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-01 Debabrata Chandra , Supratik Pal

A thermal gravitational wave background can be produced in the early Universe if a radiation dominated epoch precedes the usual inflationary stage. This background provides a unique way to study the initial state of the Universe. We discuss…

General Relativity and Quantum Cosmology · Physics 2010-03-25 W. Zhao , D. Baskaran , P. Coles

Cosmic microwave background (CMB) anisotropy may result from both scalar and tensor perturbations. For a sufficiently narrow range of angular scales, CMB perturbations can be characterized by four parameters. Results from the Cosmic…

Astrophysics · Physics 2009-10-22 Scott Dodelson , Lloyd Knox , Edward W. Kolb

Dynamics of long-wave isocurvature perturbations during an inflationary stage in multiple (multi-component) inflationary models is calculated analytically for the case where scalar fields producing this stage interact between themselves…

Astrophysics · Physics 2011-06-30 D. Polarski , A. A. Starobinsky

With future galaxy surveys, a huge number of Fourier modes of the distribution of the large scale structures in the Universe will become available. These modes are complementary to those of the CMB and can be used to set constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Zhiqi Huang , Licia Verde , Filippo Vernizzi

We investigate the possibility that fields coupled to the inflaton can influence the primordial spectrum of density perturbations through their coherent motion. For example, the second field in hybrid inflation might be oscillating at the…

Astrophysics · Physics 2008-11-26 J. M. Cline

We place functional constraints on the shape of the inflaton potential from the cosmic microwave background through a variant of the generalized slow roll approximation that allows large amplitude, rapidly changing deviations from…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-01 Cora Dvorkin , Wayne Hu