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Related papers: Planck, LHC, and $\alpha$-attractors

200 papers

Single-field models of $\alpha$-attractor quintessential inflation provide a unified picture of the two periods of early- and late-time cosmic acceleration, where both inflation and dark energy are described by a single scalar degree of…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-05 Yashar Akrami , Santiago Casas , Senwen Deng , Valeri Vardanyan

The recent results on the baryon acoustic oscillations measurements from the DESI collaboration have shown tantalizing hints for a time-evolving dark energy equation of state parameter $w(z)$, with a statistically significant deviation from…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-14 George Alestas , Marienza Caldarola , Sachiko Kuroyanagi , Savvas Nesseris

We revisit phenomenological as well as string-theoretical aspects of D-brane inflation cosmological models. Phenomenologically these models stand out on par with $\alpha$-attractors, as models with Planck-compatible values of $n_s$, moving…

High Energy Physics - Theory · Physics 2019-01-30 Renata Kallosh , Andrei Linde , Yusuke Yamada

Minimal chaotic models of D-term inflation predicts too large primordial tensor perturbations. Although it can be made consistent with observations utilizing higher order terms in the K\"ahler potential, expansion is not controlled in the…

High Energy Physics - Theory · Physics 2016-05-13 Kazunori Nakayama , Ken'ichi Saikawa , Takahiro Terada , Masahide Yamaguchi

Cosmological perturbations are generally described by quantum fields on (curved but) classical space-times. While this strategy has a large domain of validity, it can not be justified in the quantum gravity era where curvature and matter…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Ivan Agullo , Abhay Ashtekar , William Nelson

We place observational constraints on slow-variation single-field inflationary models by carrying out the cosmological Monte Carlo simulation with the recent data of Planck combined with the WMAP large-angle polarization, baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-12 Shinji Tsujikawa , Junko Ohashi , Sachiko Kuroyanagi , Antonio De Felice

A new family of inflation models is introduced and studied. The models are characterised by a scalar potential which, far from the origin, approaches an inflationary plateau in a power-law manner, while near the origin becomes monomial, as…

High Energy Physics - Phenomenology · Physics 2015-11-20 Konstantinos Dimopoulos

We define a general class of superconformal inflationary attractor models studied in our previous papers [1,2], which include, among others, inflationary models of 'induced gravity' which were argued to retain perturbative unitarity up to…

High Energy Physics - Theory · Physics 2015-06-18 Renata Kallosh

We describe a broad class of multi-field inflationary models with spontaneously broken conformal invariance. It generalizes the recently discovered class of cosmological attractors with a single inflaton field. In the new multi-field…

High Energy Physics - Theory · Physics 2015-06-17 Renata Kallosh , Andrei Linde

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

On the basis of the relativistic kinetic theory the mathematical model of cosmological plasmas with an attraction of the like charged scalar particles is formulated. It is shown, that cosmological the model, based on a classical scalar…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Yu. G. Ignat'ev

In this PhD thesis, we investigate generic features of inflation which are strictly related to fundamental aspects of UV-physics scenarios, such as string theory or supergravity. After a short introduction to standard and inflationary…

High Energy Physics - Theory · Physics 2016-07-06 Marco Scalisi

It has been shown that sub-Planckian models of inflation require initial homogeneity on super-Hubble scales under certain commonly held assumptions. Here I remark on the possible implications of this result for inflationary cosmology.

Astrophysics · Physics 2009-10-31 Tanmay Vachaspati

In the scalar-tensor theory of gravitation it seems nontrivial to establish if solutions of the cosmological equations in the presence of a cosmological constant behave as attractors independently of the initial values. We develop a general…

High Energy Physics - Theory · Physics 2009-11-06 Kei-ichi Maeda , Yasunori Fujii

A generic outcome of theories with scalar-tensor coupling is the existence of inflationary attractors, either power-law or de Sitter. The fluctuations arising during this phase are Gaussian and their spectrum depends on the wavenumber $k$…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Luca Amendola , Diego Bellisai , Franco Occhionero , Rome Astronomical Observatory

We continue developing cosmological models involving nilpotent chiral superfields, which provide a simple unified description of inflation and the current acceleration of the universe in the supergravity context. We describe here a general…

High Energy Physics - Theory · Physics 2015-03-31 Renata Kallosh , Andrei Linde , Marco Scalisi

Applying the anholonomic frame deformation method, we construct various classes of cosmological solutions for effective Einstein -- Yang-Mills -- Higgs, and two measure theories. The types of models considered are…

General Physics · Physics 2017-10-19 Subhash Rajpoot , Sergiu I. Vacaru

In this paper we show that the new approach to the embedding of the inflationary potentials into supergravity, presented in a quite recent paper [11] of Ferrara, Kallosh, Linde and Porrati can be formulated within the framework of standard…

High Energy Physics - Theory · Physics 2016-01-20 P. Fre , A. S. Sorin

In the era of Planck cosmology, the inflationary paradigm is best fitted toward the cosmological attractor scenarios, including the induced inflation, universal attractors, conformal attractors, and special attractors that are cataloged as…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-28 Chengjie Fu , Di Lu , Shao-Jiang Wang

We construct the simplest inflationary $\alpha$-attractor models in supergravity: it has only one scalar, the inflaton. There is no sinflaton since the inflaton belongs to an orthogonal nilpotent superfield where the sinflaton depends on…

High Energy Physics - Theory · Physics 2019-05-01 Renata Kallosh , Yusuke Yamada