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Related papers: Polynomial $\alpha$-attractors

200 papers

Supersymmetric theories often include the non-compact directions in the field space along which the tree level potential grows only up to a certain limited value (determined by the mass scale of the theory) and then stays constant for the…

High Energy Physics - Phenomenology · Physics 2009-10-28 Gia Dvali

Cosmological $\alpha$-attractors are observationally favored due to the asymptotic flatness of the potential. Since its flatness induces the negative pressure even after inflation, the coherent oscillation of the inflaton field could…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-16 Fuminori Hasegawa , Jeong-Pyong Hong

We study post-inflationary evolution in $\alpha$-attractor T-models of inflation. We consider the dynamics of both scalar fields present in these models: the inflaton and the spectator, as a negative field-space curvature may lead to…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-12 Tomasz Krajewski , Krzysztof Turzyński

At high e-foldings of expansion, the inflation with the quartic potential exhibits the parametric attractor governed by the slowly running Hubble rate. This quasiattractor simplifies the analysis of predictions for the inhomogeneity…

General Relativity and Quantum Cosmology · Physics 2008-06-11 V. V. Kiselev , S. A. Timofeev

In this paper, we apply reconstruction techniques to recover the potential parameters for a particular class of single-field models, the $\alpha$-attractor (supergravity) models of inflation. This also allows to derive the inflaton vacuum…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-28 A. Di Marco , P. Cabella , N. Vittorio

In inflationary scenarios with more than one scalar field, inflation may proceed even if each of the individual fields has a potential too steep for that field to sustain inflation on its own. We show that scalar fields with exponential…

Astrophysics · Physics 2010-01-06 Andrew R Liddle , Anupam Mazumdar , Franz E Schunck

A new family of inflationary models is introduced and analysed. The behaviour of the parameters characterising the models suggest preferred values, which generate the most interesting testable predictions. Results are further improved if…

High Energy Physics - Phenomenology · Physics 2016-09-20 Konstantinos Dimopoulos , Charlotte Owen

Multi-field inflation can be inherently non-predictive, with the exception of models with strong attractors. In this work, we focus on models with multiple scalar fields that are non-minimally coupled to the space-time Ricci curvature…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-18 Perseas Christodoulidis , Robert Rosati , Evangelos I. Sfakianakis

We study DBI inflation based upon a general model characterized by a power-law flow parameter $\epsilon(\phi)\propto\phi^{\alpha}$ and speed of sound $c_s(\phi)\propto\phi^{\beta}$, where $\alpha$ and $\beta$ are constants. We show that in…

General Relativity and Quantum Cosmology · Physics 2009-10-02 Dennis Bessada , William H. Kinney , Konstantinos Tzirakis

Processes of particle production during inflation can increase the amplitude of the scalar metric perturbations. We show that such a mechanism can naturally arise in supergravity models where an axion-like field, whose potential is…

High Energy Physics - Phenomenology · Physics 2021-07-07 Michael A. Roberts , Lorenzo Sorbo

We investigate the cosmological inflation in a class of supergravity models that are generalizations of non-supersymmetric $R^2$ models. Although such models have been extensively studied recently, especially after the launch of the PLANCK…

High Energy Physics - Theory · Physics 2015-06-23 G. A. Diamandis , B. C. Georgalas , K. Kaskavelis , P. Kouroumalou , A. B. Lahanas , G. Pavlopoulos

We consider two classes of non-minimally coupled inflation models; those with a quadratic coupling of the inflaton to gravity, and the `Universal Attractor' models where the coupling is connected to the potential. We make a detailed…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 David C. Edwards , Andrew R. Liddle

In this article we study the asymptotic behavior of solutions, in sense of global pullback attractors, of the evolution system $$ \begin{cases} u_{tt} +\eta\Delta^2 u+a(t)\Delta\theta=f(t,u), & t>\tau,\ x\in\Omega,\\ \theta_t-\kappa\Delta…

Analysis of PDEs · Mathematics 2016-09-05 Flank D. M. Bezerra , Vera L. Carbone , Marcelo J. D. Nascimento , Karina Schiabel

We show explicitly how the T model, E model, and Hilltop inflations are obtained from the general scalar-tensor theory of gravity with arbitrary conformal factors in the strong coupling limit. We argue that $\xi$ attractors can give any…

General Relativity and Quantum Cosmology · Physics 2016-12-07 Zhu Yi , Yungui Gong

The simplest $\alpha$-attractor $T$ model is given by the potential $V=V_0\tanh^2(\lambda\phi/M_{pl})$. However its generalization to the class of models of the type $V = V_0 \tanh^p (\lambda \phi/M_{pl})$ is difficult to interpret as a…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-13 Gabriel German

We propose a multi-natural inflation model in which the single-field inflaton potential consists of two or more sinusoidal potentials that are comparable in size, but have different periodicity with a possible non-zero relative phase. The…

High Energy Physics - Phenomenology · Physics 2014-05-30 Michael Czerny , Fuminobu Takahashi

We consider two non-canonical scalar fields (tachyon and DBI) with E-model type of the potential. We study cosmological inflation in these models to find possible $\alpha$-attractors. We show that similar to the canonical scalar field case,…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Narges Rashidi , Kourosh Nozari

We consider a certain two-parameter family of automorphisms of the affine plane over a complete, locally compact non-Archimedean field. Each of these automorphisms admits a chaotic attractor on which it is topologically conjugate to a full…

Dynamical Systems · Mathematics 2020-01-27 Clayton Petsche

We clarify inflaton models by considering them as effective field theories in the Ginzburg-Landau spirit.In this new approach, the precise form of the inflationary potential is constructed from the present WMAP data, and a useful scheme is…

Astrophysics · Physics 2009-11-10 D. Cirigliano , H. J. de Vega , N. G. Sanchez

We prove existence of global attractors for damped hyperbolic equations of the form $$\aligned \eps u_{tt}+\alpha(x) u_t+\beta(x)u- \sum_{ij}(a_{ij}(x) u_{x_j})_{x_i}&=f(x,u),\quad x\in \Omega, t\in[0,\infty[, u(x,t)&=0,\quad x\in \partial…

Analysis of PDEs · Mathematics 2007-05-23 Martino Prizzi , Krzysztof P. Rybakowski