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Related papers: Does Planck really rule out monomial inflation?

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We show that if the inflaton has a non-minimal coupling to gravity and the Planck scale is dynamically generated, the results of Coleman-Weinberg inflation are confined in between two attractor solutions: quadratic inflation, which is ruled…

High Energy Physics - Phenomenology · Physics 2016-01-18 Kristjan Kannike , Antonio Racioppi , Martti Raidal

In the context of single field inflation, models with a quadratic potential and models with a natural potential with subplanckian decay constant are in tension with the Planck data. We show that, when embedded in a two-field model with an…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-15 Ana Achucarro , Vicente Atal , Yvette Welling

In the context of inflationary models with a pre-inflationary stage, in which the Einstein equations are obeyed, the weak energy condition is satisfied, and spacetime topology is trivial, we argue that homogeneity on super-Hubble scales…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Tanmay Vachaspati , Mark Trodden

The previously proposed class of phenomenological inflationary models in which the assumption of inflaton slow-roll is replaced by the more general, constant-roll condition is compared with the most recent cosmological observational data,…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-28 Hayato Motohashi , Alexei A. Starobinsky

We consider several gauge invariant higher dimensional operators that couple gravity, gauge fields and scalar or fermionic fields and thus break conformal invariance. In particular, we consider terms that break conformal invariance by the…

Astrophysics · Physics 2007-05-23 Tomislav Prokopec

Scalar density cosmological perturbations, spectral indices and reheating in a chaotic inflationary universe model, in which a higher derivative term is added, are investigated. This term is supposed to play an important role in the early…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Victor H. Cardenas , Sergio del Campo , Ramon Herrera

We consider curved space quantum corrections to the equations of motion of the inflaton field in the early Universe. Using the stochastic formalism in phase space, we demonstrate that the quantum corrected evolution of the inflaton can…

High Energy Physics - Phenomenology · Physics 2009-09-25 Zygmunt Lalak , Rudolf Poppe

In this paper, we reconstruct viable inflationary models by starting from spectral index and tensor-to-scalar ratio from Planck observations. We analyze three different kinds of models: scalar field theories, fluid cosmology and…

General Relativity and Quantum Cosmology · Physics 2015-09-21 Ratbay Myrzakulov , Lorenzo Sebastiani , Sergio Zerbini

We discuss cosmological inflation in the minimal Wess-Zumino model with a single massive chiral supermultiplet. With suitable parameters and assuming a plausible initial condition at the start of the inflationary epoch, the model can yield…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-16 Djuna Croon , John Ellis , Nick E. Mavromatos

We investigate the insensitivity of the predictions of inflationary models with respect to modifications of Planck energy physics. The modification we consider consists in replacing the usual dispersion relation by nonlinear ones. This way…

Astrophysics · Physics 2009-11-06 J. C. Niemeyer , R. Parentani

We introduce a new class of models of chaotic inflation inspired by the superconformal approach to supergravity. This class of models allows a functional freedom of choice of the inflaton potential V = |f(\phi)|^2. The simplest model of…

High Energy Physics - Theory · Physics 2010-11-22 Renata Kallosh , Andrei Linde

Assisted chaotic inflation in brane cosmology is discussed. We work in the framework of Randall-Sundrum (RS) II model, in which adopting the RS condition the only parameter is the five-dimensional Planck mass. Using the scalar spectral…

High Energy Physics - Phenomenology · Physics 2008-11-26 Grigoris Panotopoulos

Observations of the temperature anisotropies in the Cosmic Microwave Background (CMB) radiation show that the models of inflation with the monomial potentials are inconsistent with the allowed $n_s-r$ bounds. However certain monomial…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-17 Richa Arya , Raghavan Rangarajan

Warm inflation is, as of today, one of the best motivated mechanisms for explaining an early inflationary period. In this paper, we derive and analyze the current bounds on warm inflation with a monomial potential $U\propto \phi^p$, using…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 Luca Visinelli

Identifying the inflaton with a pseudo-Goldstone boson explains the flatness of its potential. Successful Goldstone Inflation should also be robust against UV corrections, such as from quantum gravity: in the language of the effective field…

High Energy Physics - Phenomenology · Physics 2015-09-14 Djuna Croon , Veronica Sanz , Jack Setford

We use data from the nominal Planck mission to constrain modulations in the primordial power spectrum associated with monodromy inflation. The largest improvement in fit relative to the unmodulated model has \Delta\chi^2~10 and we find no…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Richard Easther , Raphael Flauger

Assuming the space dimension is not constant but decreases during the expansion of the Universe, we study chaotic inflation with the potential $m^2 \phi^2/2$. We write down field equations in the slow-roll approximation and define slow…

Astrophysics · Physics 2009-10-31 Forough Nasseri , Sohrab Rahvar

We study the chaotic inflation in the context of a gravity theory where the Friedman equation is modified, inspired by the polytropic gas equation of state. It is seen that in the $n=1$ case for the polytropic index the inflaton field at…

General Relativity and Quantum Cosmology · Physics 2013-10-29 M. R. Setare , F. Darabi

We point out that the ability of some models of inflation, such as Higgs inflation and the universal attractor models, in reproducing the available data is due to their relation to the Starobinsky model of inflation. For large field values,…

High Energy Physics - Theory · Physics 2014-03-05 Alex Kehagias , Azadeh Moradinezhad Dizgah , Antonio Riotto

We present uniform rate inflation in a modified $f(T, \mathcal{T}) $ gravity. It is found that early inflation can be realized even with a scalar field field with a quadratic potential and a negative cosmological constant. We construct…

General Relativity and Quantum Cosmology · Physics 2025-07-02 Priyanka Mandal , B. C. Paul
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