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We consider the hypothesis that nonlocal, omnidirectional, causally-coherent quantum entanglement of inflationary horizons may account for some well-known measured anomalies of Cosmic Microwave Background (CMB) anisotropy on large angular…

General Relativity and Quantum Cosmology · Physics 2022-02-16 Craig Hogan , Stephan S. Meyer

We study the non-Gaussianities generated by light axions, or compact scalar fields, during inflation. To correctly calculate their impact on primordial statistics, we will argue that it is necessary to account for the periodicity, or gauge…

High Energy Physics - Theory · Physics 2025-10-28 Priyesh Chakraborty

A detection of primordial non-Gaussianity could transform our understanding of the fundamental theory of inflation. The precision promised by upcoming CMB and large-scale structure surveys raises a natural question: if a detection given a…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-04 Joyce Byun , Rachel Bean

In this paper we mainly focus on the curvature perturbation generated at the end of multi-field inflation, such as the multi-brid inflation. Since the curvature perturbation is produced on the super-horizon scale, the bispectrum and…

High Energy Physics - Theory · Physics 2010-04-15 Qing-Guo Huang

We consider cosmological inflationary models in which vector fields play some role in the generation of the primordial curvature perturbation $\zeta$. Such models are interesting because the involved vector fields naturally seed statistical…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-19 Juan P. Beltran Almeida , Yeinzon Rodriguez , Cesar A. Valenzuela-Toledo

Most models of inflation have small parameters, either to guarantee sufficient inflation or the correct magnitude of the density perturbations. In this paper we show that, in supersymmetric theories with weak scale supersymmetry breaking,…

High Energy Physics - Phenomenology · Physics 2009-09-15 Lisa Randall , Marin Soljacic , Alan Guth

Primordial non-Gaussianities (PNGs) are imprints in the initial density field sourced by the dynamics of inflation. These dynamics can induce scale dependence, oscillations, and other features in the primordial bispectrum. We analyze a…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-24 Dhayaa Anbajagane , Hayden Lee

In arXiv:0908.4089, we have proposed a model where natural inflation is realized on a steep potential as a consequence of the interaction of the inflaton with gauge fields through an axion-like coupling. In the present work we study the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Mohamed M. Anber , Lorenzo Sorbo

The standard model of cosmology with nearly Gaussian, isotropic, scale invariant and adiabatic initial conditions describes the cosmological observations well. However, the study of any deviation from the mentioned conditions will open up a…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-31 Mohammad Ansari Fard , Shant Baghram

We present an inflationary model that is geodesically complete and does not suffer from the transplanckian problem. In most inflationary models, massless (conformal) scalar field fluctuations in a deSitter background gives rise to a…

High Energy Physics - Theory · Physics 2009-09-02 Tirthabir Biswas , Stephon Alexander

Anisotropies in distortions to the frequency spectrum of the cosmic microwave background (CMB) can be created through spatially varying heating processes in the early Universe. For instance, the dissipation of small-scale acoustic modes…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Jens Chluba , Emanuela Dimastrogiovanni , Mustafa A. Amin , Marc Kamionkowski

The inflationary paradigm is extremely successful regarding predictions of temperature anisotropies in the CMB. However, inflation also makes predictions for a CMB B-mode polarization, which has not been detected. Moreover, the standard…

General Relativity and Quantum Cosmology · Physics 2018-07-24 Gabriel León , Abhishek Majhi , Elias Okon , Daniel Sudarsky

We introduce the real space correlation function of $B$-mode polarization of the cosmic microwave background (CMB) as a probe of superhorizon tensor perturbations created by inflation. By causality, any non-inflationary mechanism for…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-15 Daniel Baumann , Matias Zaldarriaga

We give a detailed presentation of a recently proposed mechanism of generating the energy scale of inflation by loop effects in quantum cosmology. We discuss the quantum origin of the early inflationary Universe from the no-boundary and…

General Relativity and Quantum Cosmology · Physics 2011-08-17 A. O. Barvinsky , A. Yu. Kamenshchik , I. V. Mishakov

We consider an alternative scenario of inflation which can account for a spatially open universe. It is similar to the old inflation in which the bubble nucleation occurs in the sea of false vacuum, but differs from it in that the second…

Astrophysics · Physics 2016-08-30 Kazuhiro Yamamoto , Misao Sasaki , Takahiro Tanaka

In this work we study the imprints of bubble nucleation on primordial inflationary perturbations. We assume that the bubble is formed via the tunneling of a spectator field from the false vacuum of its potential to its true vacuum. We…

General Relativity and Quantum Cosmology · Physics 2017-12-27 Hassan Firouzjahi , Sadra Jazayeri , Asieh Karami , Tahereh Rostami

The presence of additional particles during inflation leads to non-Gaussianity in late-time correlators of primordial curvature perturbations. The shape and amplitude of this signal depend on the mass and spin of the extra particles.…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-16 Azadeh Moradinezhad Dizgah , Cora Dvorkin

We show that perturbations generated during the anisotropic pre-inflationary stage of cosmic evolution may affect cosmological observations today for a certain range of parameters. Due to the anisotropic nature of the universe during such…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-15 Pavan K. Aluri , Pankaj Jain

We propose a "multi-stream" inflation model, which is a double field model with spontaneous breaking and restoration of an approximate symmetry. We calculate the density perturbation and non-Gaussianity in this model. We find that this…

High Energy Physics - Theory · Physics 2014-11-18 Miao Li , Yi Wang

We explore extensions of hybrid inflationary models in the context of supersymmetric D-term inflation. We point out that a large variety of inflationary scenarios can be encountered when the field content is extended. It is not only…

High Energy Physics - Phenomenology · Physics 2008-11-26 Francis Bernardeau , Tristan Brunier