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Related papers: An alternative attractor in gauged NJL inflation

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By solving the compositeness condition, under which the Yukawa-type model coincides the NJL type model, we obtain the expressions for the effective coupling constants in terms of the compositeness scale at the next-to-leading order in 1/N.…

High Energy Physics - Phenomenology · Physics 2007-05-23 Keiichi Akama

In this work we study the cosmological attractor models of inflation in connection with certain scalar-tensor theories of gravity, e.g $f(R)$ gravity and Brans-Dicke theory. For some particular choices of the functional degrees of freedom…

General Relativity and Quantum Cosmology · Physics 2018-06-13 Sukannya Bhattacharya , Kumar Das , Koushik Dutta

Recently we identified a new class of (super)conformally invariant theories which allow inflation even if the scalar potential is very steep in terms of the original conformal variables. Observational predictions of a broad class of such…

High Energy Physics - Theory · Physics 2015-06-16 Renata Kallosh , Andrei Linde

We construct $\alpha$-attractor versions of hybrid inflation models. In these models, the potential of the inflaton field $\varphi$ is uplifted by the potential of the second field $\chi$. This uplifting ends due to a tachyonic instability…

High Energy Physics - Theory · Physics 2022-08-31 Renata Kallosh , Andrei Linde

We study a variant of the Chromo-Natural Inflation (CNI) mechanism in which the inflaton interacts only gravitationally with the CNI fields. Integrating out all the non-dynamical scalar fields of the model results in a coupling between the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 Alexandros Papageorgiou , Marco Peloso , Caner Unal

A new model of inflation is described. An unusual form for the inflationary potential is obtained because the inflaton corresponds to a non-trivial path in the configuration space of the two real scalar fields of the model. The model…

Astrophysics · Physics 2009-10-22 Ewan D. Stewart

We investigate the effect of mesonic fluctuations on the pion propagator in the Nambu-Jona-Lasinio (NJL) model by explicitly taking into account 1/N_c corrections. Because of the non-renormalizability of the model we have to regularize the…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Oertel , M. Buballa , J. Wambach

We develop a new class of cosmological attractors which are compatible with the recent ACT results. They are based on two types of fractional Kaehler potentials, K, for a gauge-singlet inflaton phi which reduce, along the inflationary path,…

High Energy Physics - Phenomenology · Physics 2025-10-03 C. Pallis

We show explicitly how the E model attractor is obtained from the general scalar-tensor theory of gravity with arbitrary conformal factors in the strong coupling limit. By using conformal transformations, any attractor with the observables…

General Relativity and Quantum Cosmology · Physics 2018-01-24 Zhu Yi , Yungui Gong

We discuss a new mechanism to enhance the spectrum of primordial tensor fluctuations in single field inflationary scenarios. The enhancement relies on a transitory non-attractor inflationary phase, which amplifies the would-be decaying…

General Relativity and Quantum Cosmology · Physics 2019-02-22 Maria Mylova , Ogan Özsoy , Susha Parameswaran , Gianmassimo Tasinato , Ivonne Zavala

After Planck 2013, a broad class of inflationary models called \alpha-attractors was developed which has universal observational predictions. For small values of the parameter \alpha, the models have good consistency with the recent CMB…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-22 Mehdi Eshaghi , Moslem Zarei , Nematollah Riazi , Ahmad Kiasatpour

We revisit an extension of the well-known formalism for gauge-invariant scalar metric fluctuations, to study the spectrums for both, the inflaton and gauge invariant (scalar) metric fluctuations in the framework of a single field…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Mariano Anabitarte , Mauricio Bellini

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ralf Hofmann , Mathias Th. Keil

The $\alpha$-attractor models are some of the most interesting models of inflation from the point of view of upcoming observations in cosmology and also attractive from the point of view of supergravity. We confront representative models of…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-02 Sukannya Bhattacharya , Koushik Dutta , Mayukh R. Gangopadhyay , Anshuman Maharana

Several recent misconceptions about the measure problem in inflation and the nature of inflationary attractors are addressed. We show that within the Hamiltonian system of flat Friedmann-Lema\^itre-Robertson-Walker cosmology coupled to a…

General Relativity and Quantum Cosmology · Physics 2015-07-28 Alejandro Corichi , David Sloan

The presence of multiple fields during inflation might seed a detectable amount of non-Gaussianity in the curvature perturbations, which in turn becomes observable in present data sets like the cosmic microwave background (CMB) or the large…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-27 Sebastian Dorn , Erandy Ramirez , Kerstin E. Kunze , Stefan Hofmann , Torsten A. Enßlin

Attractor inflation is a particularly robust framework for developing inflationary models that are insensitive to the details of the potential. Such models are most often considered in the metric formulation of gravity. However, non-minimal…

General Relativity and Quantum Cosmology · Physics 2021-11-03 Alexandros Karam , Sotirios Karamitsos , Margus Saal

The equations for quintessential $\alpha$-attractor inflation with a single scalar field, radiation and matter in a spatially flat FLRW spacetime are recast into a regular dynamical system on a compact state space. This enables a complete…

General Relativity and Quantum Cosmology · Physics 2024-02-08 Artur Alho , Claes Uggla

Recent ACT data favor a higher scalar spectral index $n_s$, placing models such as $\alpha$-attractor T-models and natural Inflation in tension with current observations. We propose a K-inflation framework with a field-dependent…

General Relativity and Quantum Cosmology · Physics 2026-05-05 Milad Solbi , Daris Samart , Peera Simakachorn

In this paper we discuss symmetry breakdown in NJL model at low N_c. In particular we propose a modified NJL model that displays a symmetry breakdown and also at finite temperatures under certain conditions the chiral fluctuations in this…

High Energy Physics - Phenomenology · Physics 2009-10-31 Egor Babaev