English
Related papers

Related papers: Quantifying the 'naturalness' of the curvaton mode…

200 papers

In slow roll inflation, the running of the spectral tilt is generically proportional to the square of the deviation from scale invariance, $\alpha_s \propto (n_s-1)^2$, and it is therefore currently undetectable. We present a mechanism able…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Marco Peloso , Lorenzo Sorbo , Gianmassimo Tasinato

Curvaton reheating is studied in non-oscillatory (NO) models of inflation, with the aim to obtain bounds on the parameters of curvaton models and find out whether low scale inflation can be attained. Using a minimal curvaton model, it is…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. C. Bueno Sanchez , K. Dimopoulos

In this work we revisit $\alpha$-Starobinsky inflation, also know as $E$-model, in the light of current CMB and LSS observations. The inflaton potential in the Einstein frame for this model contains a parameter $\alpha$ in the exponential,…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-11 Saisandri Saini , Akhilesh Nautiyal

We investigate the inflaton decay and reheating period after the end of inflation in the non-minimal derivative coupling (NDC) model with chaotic potential. In general, this model is known to provide an enhanced slow-roll inflation caused…

General Relativity and Quantum Cosmology · Physics 2016-07-20 Yun Soo Myung , Taeyoon Moon

We compute the growth of the mean square of quantum fluctuations of test fields with small effective mass during a slowly changing, nearly de Sitter stage which took place in different inflationary models. We consider a minimally coupled…

High Energy Physics - Theory · Physics 2010-10-11 F. Finelli , G. Marozzi , A. A. Starobinsky , G. P. Vacca , G. Venturi

We investigate the effects of large inhomogeneities in both the inflaton field and its momentum. We find that in general, large kinetic perturbations reduce the number of e-folds of inflation. In particular, we observe that inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-13 Matthew Elley , Josu C. Aurrekoetxea , Katy Clough , Raphael Flauger , Panagiotis Giannadakis , Eugene A. Lim

Best-fit values of the spectral index of the curvature perturbation are presented, assuming the $\Lambda$CDM cosmology. Apart from the spectral index, the parameters are the Hubble parameter, the total matter density and the baryon density.…

Astrophysics · Physics 2016-08-30 L. Covi , D. H. Lyth

We develop a variant of the generalized slow roll approach for calculating the curvature power spectrum that is well-suited for order unity deviations in power caused by sharp features in the inflaton potential. As an example, we show that…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-07 Cora Dvorkin , Wayne Hu

Cosmic Microwave Background (CMB) is an important probe for understanding the inflationary era of the Universe. We consider the Perturbed Power Law (PPL) model of inflation which is a soft deviation from Power Law (PL) inflationary model.…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-03 Suvodip Mukherjee , Santanu Das , Minu Joy , Tarun Souradeep

The present measurement of the standard model (SM) parameters suggests that the Higgs effective potential has a maximum at the intermediate scale, and the electroweak (EW) vacuum is not absolutely stable. The simplest possibility for…

High Energy Physics - Phenomenology · Physics 2022-11-08 Wen Yin

We study inflation driven by a scalar potential arising from composite-sector dynamics, inspired by generalized composite Higgs models. The introduction of a non-minimal coupling, possessing the same functional form as the potential,…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-01 Marco Merchand

The scenario of constant-roll inflation is studied where the inflaton is a scalar field with modified kinetic term, known as non-canonical scalar field. This modification leads to some changes in the slow-roll parameters, and also by taking…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Abolhassan Mohammadi , Khaled Saaidi , Haidar Sheikhahmadi

We consider Higgs inflation with an $\alpha R^2$ term. It adds a new scalar degree of freedom, which leads to a two-field model of inflation. We do a complete slow-roll analysis of the three-dimensional parameter space of the $R^2$…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-22 Vera-Maria Enckell , Kari Enqvist , Syksy Rasanen , Lumi-Pyry Wahlman

The eternally inflating multiverse provides a consistent framework to understand coincidences and fine-tuning in the universe. As such, it provides the possibility of finding another coincidence: if the amount of slow-roll inflation was…

High Energy Physics - Theory · Physics 2013-05-30 Alan H. Guth , Yasunori Nomura

We investigate the inflation and reheating phenomenology in scalar-Einstein-Gauss-Bonnet theory of gravity where a scalar field non-minimally couples with the Gauss-Bonnet (GB) curvature term. Regarding the inflationary phenomenology, we…

General Relativity and Quantum Cosmology · Physics 2023-05-31 Sergei D. Odintsov , Tanmoy Paul

Determining the energy scale of inflation is crucial to understand the nature of inflation in the early Universe. We place observational constraints on the energy scale of the observable part of the inflaton potential by combining the…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-12 Zong-Kuan Guo , Dominik J. Schwarz , Yuan-Zhong Zhang

We propose a new version of the hybrid inflation scenario that produces a significantly tilted n>1 spectrum of curvature perturbations. This may happen in supersymmetric models where the inflaton field acquires a mass proportional to the…

Astrophysics · Physics 2009-09-29 Juan Garcia-Bellido , Andrei Linde

From the damping of the Cosmic Microwave Background Radiation (CMB) anisotropy power spectrum at large scale and the recent accelerating expansion of the Universe, we find that, there may be a largest scale which we can detect in the…

Astrophysics · Physics 2016-08-30 Wen Zhao , Yang Zhang

Using the techniques of out-of-equilibrium field theory, we study the influence on the properties of cosmological perturbations generated during inflation on observable scales coming from fluctuations corresponding today to scales much…

High Energy Physics - Theory · Physics 2009-11-10 Sabino Matarrese , Marcello A. Musso , Antonio Riotto

By using the newtonian gauge, we re-confirm that, as in the minimal case, the re-scaled Mukhanov-Sasaki variable is conserved leading to a constraint equation for the Newtonian potential. However, conversely to the minimal case, in…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 Cristiano Germani , Nina Kudryashova , Yuki Watanabe