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Related papers: Natural Inflation From Fermion Loops

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In the context of Palatini gravity, $F(R+X)$ models, with X the inflaton kinetic term, are characterized by the appealing property of generating asymptotically flat inflaton potentials, exactly like the more commonly studied Palatini $F(R)$…

General Relativity and Quantum Cosmology · Physics 2025-12-22 N. Bostan , R. H. Dejrah , C. Dioguardi , A. Racioppi

Out-of-equilibrium, non-perturbative, quantum effects significantly modify the standard picture of inflation in a wide class of models including new, natural, and hybrid inflation. We find that the quantum evolution of a single real…

High Energy Physics - Phenomenology · Physics 2010-01-06 D. Cormier , R. Holman

An estimate of the one-loop correction to the power spectrum of the primordial curvature perturbation is given, assuming it is generated during a phase of single-field, slow-roll inflation. The loop correction splits into two parts, which…

Astrophysics · Physics 2010-02-09 David Seery

In a one-generation fermion condensate scheme of electroweak symmetry breaking, it is proven based on Schwinger-Dyson equation in the real-time thermal field theory in the fermion bubble diagram approximation that, at finite temperature $T$…

High Energy Physics - Theory · Physics 2016-09-06 Bang-Rong Zhou

We propose that inflation and dark matter have a common origin, connected to the neutrino mass generation scheme. As a model we consider spontaneous breaking of global lepton number within the seesaw mechanism. We show that it provides an…

High Energy Physics - Phenomenology · Physics 2014-10-01 Sofiane M. Boucenna , Stefano Morisi , Qaisar Shafi , Jose W. F. Valle

A scenario of leptogenesis was introduced in [1] which works during inflationary period within standard model of particle physics setup. In this scenario lepton number is created by the gravitational chiral anomaly which has a non-zero…

High Energy Physics - Theory · Physics 2018-08-21 Azadeh Maleknejad , Mahdiyar Noorbala , M. M. Sheikh-Jabbari

We explore the possibility that inflation is driven by supersymmetry breaking with the superpartner of the goldstino (sgoldstino) playing the role of the inflaton. Moreover, we impose an R-symmetry that allows to satisfy easily the…

High Energy Physics - Theory · Physics 2017-11-22 Ignatios Antoniadis , Auttakit Chatrabhuti , Hiroshi Isono , Rob Knoops

We present a new approximation scheme that allows us to increase the accuracy of analytical predictions of the power spectra of inflationary perturbations for two specific classes of inflationary models. Among these models are chaotic…

Astrophysics · Physics 2015-06-24 C. A. Terrero-Escalante , D. J. Schwarz , A. A. Garcia

I report on work done with Tomislav Prokopec (Heidelberg, CERN). We computed the one loop self-energy of a massless fermion during inflation. When the fermion is free it experiences only a small amount of inflationary particle production…

Astrophysics · Physics 2007-05-23 R. P. Woodard

Chromo-natural inflation (CNI) is an inflationary model where an axion coupled with SU$(2)$ gauge fields acts as the inflaton. In CNI, the gauge fields have nonzero vacuum expectation values (VEVs), which results in the enhancement of…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-03 Tomohiro Fujita , Kaname Imagawa , Kai Murai

Phantom Cosmology provides an unique opportunity to "connect" the phantom driven (low en- ergy meV scale) dark energy phase to the (high energy GUT scale) inflationary era. This is possible because the energy density increases in phantom…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Cosmin Ilie , Tirthabir Biswas , Katherine Freese

We propose a chaotic inflation model in supergravity. In the model the K\"ahler potential has a Nambu-Goldstone-like shift symmetry of the inflaton chiral multiplet which ensures the flatness of the inflaton potential beyond the Planck…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Kawasaki , Masahide Yamaguchi , T. Yanagida

We propose an inflationary scenario, M-flation, in which inflation is driven by three $N\times N$ hermitian matrices $\Phi_i, i=1,2,3$. The inflation potential of our model, which is strongly motivated from string theory, is constructed…

High Energy Physics - Theory · Physics 2010-10-13 Amjad Ashoorioon , Hassan Firouzjahi , M. M. Sheikh-Jabbari

We demonstrate that "natural inflation", also known as "axion inflation", can be compatible with Planck 2018 measurements of the cosmic microwave background, while predicting an exponentially small tensor-to-scalar ratio, e.g., $r\sim…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-16 Dario L. Lorenzoni , David I. Kaiser , Evan McDonough

We examine the oscillon formation in a recently proposed inflation model of the pure natural inflation, where the inflaton is an axion that couples to a strongly-coupled pure Yang-Mills theory. The plateau of the inflaton potential, which…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-14 Jeong-Pyong Hong , Masahiro Kawasaki , Masahito Yamazaki

Inflation is the currently accepted paradigm for the beginnings of the Universe. To explain the observed almost scale invariant spectrum of density perturbations with only a slight spectral tilt, inflation must have been "slow roll", that…

High Energy Physics - Theory · Physics 2021-01-07 Hao Geng

We review recent developments in the theory of inflation and cosmological perturbations produced from inflation. After a brief introduction of the standard, single-field slow-roll inflation, and the curvature and tensor perturbations…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-31 Misao Sasaki

We consider inflation driven by an axion-like particle coupled to an SU(2) gauge sector via a Chern-Simons term. Known as chromo-natural inflation, this scenario is in tension with CMB observations. In order to remedy this fact and preserve…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-21 Ema Dimastrogiovanni , Matteo Fasiello , Martino Michelotti , Lucas Pinol

On the one hand, inflation is an extremely convincing scenario: it solves most cosmological paradoxes and generates fluctuations that became the seeds for the growth of structures. It, however, suffers from a "naturalness" problem:…

General Relativity and Quantum Cosmology · Physics 2011-08-04 Aurelien Barrau

We propose an inflation scenario with three independent stages of cold, warm and thermal inflation, respectively, driven by different scalar fields, motivated by the large number of such fields predicted in most extensions of the Standard…

High Energy Physics - Phenomenology · Physics 2024-10-16 Paulo B. Ferraz , João G. Rosa