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Related papers: A General Framework of Automorphic Inflation

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Seemingly unrelated models of inflation that originate from different physical setups yield, in some cases, identical predictions for the currently constrained inflationary observables. In order to classify the available models, we propose…

High Energy Physics - Phenomenology · Physics 2017-04-19 Laur Järv , Kristjan Kannike , Luca Marzola , Antonio Racioppi , Martti Raidal , Mihkel Rünkla , Margus Saal , Hardi Veermäe

We propose a new framework for multi-field inflation in which a nearly constant potential energy is maintained during inflation before decreasing rapidly, in a manner analogous to a classical top spinning upright for a long time before…

High Energy Physics - Phenomenology · Physics 2012-08-27 Alejandro Jenkins , Takemichi Okui

We explore the homogeneous background dynamics and the evolution of generated perturbations of cosmological inflation that is driven by multiple scalar fields interacting with a perfect fluid.Then we apply the method to warm inflation…

General Relativity and Quantum Cosmology · Physics 2018-04-04 Yang-Yang Wang , Jian-Yang Zhu , Xiao-Min Zhang

The shift-symmetric coupling of a pseudo-scalar particle driving inflation to gauge fields provides a unique way of probing cosmic inflation. We show for an SU(2) gauge group how a classical isotropic background gauge field develops from…

High Energy Physics - Phenomenology · Physics 2019-04-24 Valerie Domcke , Ben Mares , Francesco Muia , Mauro Pieroni

We introduce the framework of modular inflation with level structure, generalizing the level one theory considered previously to higher levels. We analyze the modular structure of CMB observables in this framework and show that the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-27 Monika Lynker , Rolf Schimmrigk

Various scenarios of the initial inflation of the universe are distinguished by the choice of a scalar field {\em potential} $U(\phi)$ which simulates a {\it temporarily} non--vanishing {\em cosmological term}. Our new method, which…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Fjodor V. ~Kusmartsev , Eckehard W. ~Mielke , Yuri N. ~Obukhov , Franz E. ~Schunck

We show that an inflationary background might be realized by using any p-form non-minimally coupled to gravity. Standard scalar field inflation corresponds to the 0-form case and vector inflation to the 1-form. Moreover, we show that the 2-…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Cristiano Germani , Alex Kehagias

We study inflection point inflation using Singularity Theory, which relates degenerate critical points of functions to their local behavior. This approach illuminates universal features of small-field models and gives analytic control over…

High Energy Physics - Theory · Physics 2011-09-28 Sean Downes , Bhaskar Dutta , Kuver Sinha

If the inflaton is a pseudo-scalar axion, the axion shift symmetry can protect the flatness of its potential from too large radiative corrections. This possibility, known as natural inflation, requires an axion scale which is greater than…

High Energy Physics - Phenomenology · Physics 2009-11-10 Jihn E. Kim , Hans Peter Nilles , Marco Peloso

I describe a general approach to characterizing cosmological inflation outside the standard slow-roll approximation, based on the Hamilton-Jacobi formulation of scalar field dynamics. The basic idea is to view the equation of state of the…

High Energy Physics - Phenomenology · Physics 2016-08-24 William H. Kinney

In this paper, we investigate models where a scalar field driving inflation is minimally coupled with gravity and it is subjected to a scalar potential. We present several examples of coupling between the field and gravity, and we furnish…

General Relativity and Quantum Cosmology · Physics 2016-03-01 Shynaray Myrzakul , Ratbay Myrzakulov , Lorenzo Sebastiani

Classic inflation, the theory described in textbooks, is based on the idea that, beginning from typical initial conditions and assuming a simple inflaton potential with a minimum of fine-tuning, inflation can create exponentially large…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-18 Anna Ijjas , Paul J. Steinhardt , Abraham Loeb

We develop a general formalism for analyzing linear perturbations in multiple-field cosmological inflation based on the gauge-ready approach. Our inflationary model consists of an arbitrary number of scalar fields with non-minimal kinetic…

Astrophysics · Physics 2009-11-13 Joydev Lahiri , Gautam Bhattacharya

It is shown in this letter that in the framework of an inhomogeneous geometry and a massive non self-interacting scalar field with spherical symmetry, one needs a homogeneous patch bigger than a dizaine of horizons in order to start…

General Relativity and Quantum Cosmology · Physics 2012-05-18 R. S. Perez , N. Pinto-Neto

We investigate inflation within $f(R,\phi)$-theories, where a dynamical scalar field is coupled to gravity. A class of models which can support early-time acceleration with the emerging of an effective cosmological constant at high…

General Relativity and Quantum Cosmology · Physics 2018-12-13 R. Myrzakulov , L. Sebastiani , S. Vagnozzi

We consider the scale-invariant inflationary model studied in [1]. The Lagrangian includes all the scale-invariant operators that can be built with combinations of $R$, $R^2$ and one scalar field. The equations of motion show that the…

General Relativity and Quantum Cosmology · Physics 2017-03-14 Giovanni Tambalo , Massimiliano Rinaldi

Transforming canonical scalars to the Einstein frame can give a multi-field generalization of pole inflation (namely, a scalar with a divergent kinetic term) at vanishing field-dependent Planck mass. However, to obtain an attractor, the…

High Energy Physics - Theory · Physics 2022-09-07 Sotirios Karamitsos , Alessandro Strumia

We investigate the inflationary attractors in models of inflation inspired from general conformal transformation of general scalar-tensor theories to the Einstein frame. The coefficient of the conformal transformation in our study depends…

General Relativity and Quantum Cosmology · Physics 2019-07-31 Khamphee Karwan , Phongpichit Channuie

Inflationary cosmology has made significant strides in understanding the physics driving the rapid expansion of the early universe. However, many inflation models with diverse potential shapes present analysis, comparison, and…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-25 Somnath Das , P K Suresh

A reformulation of inflationary model analyses appeared recently, in which inflationary observables are determined by the structure of a pole in the inflaton kinetic term rather than the shape of the inflaton potential. We comprehensively…

High Energy Physics - Theory · Physics 2016-08-04 Takahiro Terada