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Related papers: Constraints on Single-Field Inflation

200 papers

We examine a wide class of multi-field inflationary models based on fields that decay or stabilize during inflation in a staggered fashion. The fields driving assisted inflation are on flat, short stretches, before they encounter a sharp…

High Energy Physics - Theory · Physics 2009-03-27 Diana Battefeld , Thorsten Battefeld

Because the inflationary mechanism is extremely sensitive to UV-physics, the construction of theoretically robust models of inflation provides a unique window on Planck-scale physics. We review efforts to use an axion with a shift symmetry…

High Energy Physics - Theory · Physics 2015-06-15 Enrico Pajer , Marco Peloso

In the present paper, certain inflation models are shown to have large non-Gaussianity in special cases. Namely, finite length inflation models with an effective higher derivative interaction, in which slow-roll inflation is adopted as…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-26 Shiro Hirai , Tomoyuki Takami

We study the bispectrum of the curvature perturbation on uniform energy density hypersurfaces in models of inflation with two scalar fields evolving simultaneously. In the case of a separable potential, it is possible to compute the…

Astrophysics · Physics 2009-11-11 Filippo Vernizzi , David Wands

Multiple inflation is a model based on N=1 supergravity wherein there are sudden changes in the mass of the inflaton because it couples to 'flat direction' scalar fields which undergo symmetry breaking phase transitions as the universe…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Shaun Hotchkiss , Subir Sarkar

Combining the stochastic and $\delta N$ formalisms, we derive non perturbative analytical expressions for all correlation functions of scalar perturbations in single-field, slow-roll inflation. The standard, classical formulas are recovered…

High Energy Physics - Theory · Physics 2016-12-01 Vincent Vennin , Alexei A. Starobinsky

We examine cosmological inflation in a broad family of scalar-tensor models characterized by scalar-dependent non minimal kinetic couplings and Gauss-Bonnet terms. Using a slow roll-approximation, we compute in detail theoretical…

High Energy Physics - Theory · Physics 2026-05-21 A. Belhaj , H. Es-Sobbahi , M. Oualaid , E. Torrente-Lujan

Focusing on the local type primordial non-Gaussianities, we study the bispectrum and trispectrum during a non-minimal slow-roll inflation. We use the so-called $\delta N$ formalism to investigate the super-horizon evolution of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-28 Kosar Asadi , Kourosh Nozari

We study models of modular inflation of the form expected to arise from low energy effective actions of superstring theories. We argue on general grounds that the most likely models of modular slow-roll inflation are small field models in…

High Energy Physics - Theory · Physics 2009-12-15 Ido Ben-Dayan , Ram Brustein , Senarath P. de Alwis

Non-attractor inflation is known as the only single field inflationary scenario that can violate non-Gaussianity consistency relation with the Bunch-Davies vacuum state and generate large local non-Gaussianity. However, it is also known…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-08 Yi-Fu Cai , Xingang Chen , Mohammad Hossein Namjoo , Misao Sasaki , Dong-Gang Wang , Ziwei Wang

We discuss generation of non-Gaussianity in density perturbation through the super-horizon evolution during inflation by using the so-called $\delta N$ formalism. We first provide a general formula for the non-linearity parameter generated…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Takahiro Tanaka , Teruaki Suyama , Shuichiro Yokoyama

The current epoch of accelerated cosmic expansion is postulated to be driven by dark energy, which in the standard model takes the form of a cosmological constant with equation of state parameter $w=-1$. We propose an innovative perspective…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-17 Sveva Castello , Stéphane Ilić , Martin Kunz

The framework of a kind of noncanonical warm inflation is introduced, and the dynamical equations of this scenario are presented. We propose the slow roll approximations and give some redefining slow roll parameters in this scenario which…

General Relativity and Quantum Cosmology · Physics 2021-01-13 Xiao-Min Zhang , Ang Fu , Kai Li , Qian Li , Peng-Cheng Chu , Hong-Yang Ma , Jian-Yang Zhu

We present a simple effective field theory formulation of a general family of single field flux monodromy models for which strong coupling effects at large field values can flatten the potential and activate operators with higher powers of…

High Energy Physics - Theory · Physics 2018-09-12 Guido D'Amico , Nemanja Kaloper , Albion Lawrence

For simple inflationary models, we provide a consistent and complete scheme by which the macro-physical details of early universe inflation may be determined explicitly from the underlying micro-physical theory. We examine inflationary…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Cormier

We study slow-roll inflation with a Gauss-Bonnet term that is coupled to an inflaton field nonminimally. We investigate the inflationary solutions for a specific type of the nonminimal coupling to the Gauss-Bonnet term and inflaton…

General Relativity and Quantum Cosmology · Physics 2014-10-08 Seoktae Koh , Bum-Hoon Lee , Wonwoo Lee , Gansukh Tumurtushaa

We consider the generation of large-scale magnetic fields in slow-roll inflation. The inflaton field is described in a supergravity framework where the conformal invariance of the electromagnetic field is generically and naturally broken.…

Astrophysics · Physics 2009-06-23 Jerome Martin , Jun'ichi Yokoyama

We analyze the signatures of inflationary models that are coupled to strongly interacting field theories, a basic class of multifield models also motivated by their role in providing dynamically small scales. Near the squeezed limit of the…

High Energy Physics - Theory · Physics 2015-06-12 Daniel Green , Matthew Lewandowski , Leonardo Senatore , Eva Silverstein , Matias Zaldarriaga

In this letter, we propose a single-field inflation model that realizes a slow-roll-to-ultra-slow-roll transition while keeping the second slow-roll parameter smoothly varying throughout. The model is built through a minimal modification by…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-19 Diego Cruces , Minxi He , Shi Pi , Jianing Wang , Masahide Yamaguchi , Yuhang Zhu

An appealing feature of inflationary cosmology is the presence of a phase-space attractor, "slow roll", which washes out the dependence on initial field velocities. We investigate the robustness of this property under backreaction from…

General Relativity and Quantum Cosmology · Physics 2021-04-05 Julien Grain , Vincent Vennin