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Related papers: What does inflation really predict?

200 papers

We conduct a thorough study of the comoving curvature perturbation $\mathcal{R}$ in single-field inflation with two stages, represented by a piecewise quadratic potential, where both the first and second derivatives are allowed to be…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-23 Xinpeng Wang , Xiao-Han Ma , Misao Sasaki

We present constraints on canonical single-field inflation derived from WMAP five year, ACBAR, QUAD, BICEP data combined with the halo power spectrum from SDSS LRG7. Models with a non-scale-invariant spectrum and a red tilt n_s < 1 are now…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-30 Fabio Finelli , Jan Hamann , Samuel M. Leach , Julien Lesgourgues

We describe the general inflationary dynamics that can arise with a single, canonically coupled field where the inflaton potential is a 4-th order polynomial. This scenario yields a wide range of combinations of the empirical spectral…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-27 Nathan Musoke , Richard Easther

Inflation predicts a stochastic background of gravitational waves over a broad range of frequencies, from those accessible with cosmic microwave background (CMB) measurements, to those accessible directly with gravitational-wave detectors,…

Astrophysics · Physics 2008-11-26 Tristan L. Smith , Marc Kamionkowski , Asantha Cooray

Traditionally, inflationary models are analyzed in terms of parameters such as the scalar spectral index ns and the tensor to scalar ratio r, while dark energy models are studied in terms of the equation of state parameter w. Motivated by…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Stéphane Ilic , Martin Kunz , Andrew R. Liddle , Joshua A. Frieman

We show how estimates of parameters characterizing inflation-based theories of structure formation localized over the past year when large scale structure (LSS) information from galaxy and cluster surveys was combined with the rapidly…

Inflation generically predicts a stochastic background of gravitational waves over a broad range of frequencies, from those accessible with cosmic microwave background (CMB) measurements, to those accessible directly with gravitational-wave…

Astrophysics · Physics 2008-11-26 Tristan L. Smith , Marc Kamionkowski , Asantha Cooray

Most models of inflation have small parameters, either to guarantee sufficient inflation or the correct magnitude of the density perturbations. In this paper we show that, in supersymmetric theories with weak scale supersymmetry breaking,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Lisa Randall , Marin Soljacic , Alan Guth

We show that a moduli space of the form predicted by string theory, lifted by supersymmetry breaking, gives rise to successful inflation for large regions of parameter space without any modification or fine tuning. This natural realization…

High Energy Physics - Phenomenology · Physics 2009-11-10 Kenji Kadota , Ewan D. Stewart

We study single-field inflationary models with steep step-like features in the potential that lead to the temporary violation of the slow-roll conditions during the evolution of the inflaton. These features enhance the power spectrum of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-18 I. Dalianis , G. P. Kodaxis , I. D. Stamou , N. Tetradis , A. Tsigkas-Kouvelis

Any one-field inflation is actually realized in a multifield configuration because the inflaton must have couplings with other fields to reheat the universe and is coupled to all other fields at least gravitationally. In all single inflaton…

High Energy Physics - Phenomenology · Physics 2009-11-11 Masahide Yamaguchi , Jun'ichi Yokoyama

We study the linear perturbation of the recently proposed model of inflation where a uniform gauge-kinetic coupling of the inflaton to multiple vector fields breaks the cosmic no-hair conjecture while maintaining the isotropy. We derive the…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-09 Kei Yamamoto

We consider the running of the spectral index as a probe of both inflation itself, and of the overall evolution of the very early universe. Surveying a collection of simple single field inflationary models, we confirm that the magnitude of…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Peter Adshead , Richard Easther , Jonathan Pritchard , Abraham Loeb

We analyze a class of generalized inflationary models proposed in Ref. [1], known as $\beta$-exponential inflation. We show that this kind of potential can arise in the context of brane cosmology, where the field describing the size of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-15 M. A. Santos , M. Benetti , J. S. Alcaniz , F. A. Brito , R. Silva

Cosmological production of scalar, non-minimally coupled dark matter depends on the specifics of the inflationary model under consideration. We analyze both Starobinsky inflation and a quadratic potential, solve the full background…

General Relativity and Quantum Cosmology · Physics 2026-02-24 Jose A. R. Cembranos , Luis J. Garay , Álvaro Parra-López , Javier Ortega del Río

We review the main aspects of the warm inflation scenario, focusing on the inflationary dynamics and the predictions related to the primordial spectrum of perturbations, to be compared with the recent cosmological observations. We study in…

High Energy Physics - Phenomenology · Physics 2010-04-21 Mar Bastero-Gil , Arjun Berera

Inflation models can have an early phase of inflation where the evolution of the inflaton is driven by quantum fluctuations before entering the phase driven by the slope of the scalar field potential. For a Coleman-Weinberg potential this…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-06 Arjun Berera , Raghavan Rangarajan

We explore inflationary trajectories within randomly-generated two-dimensional potentials, considered as a toy model of the string landscape. Both the background and perturbation equations are solved numerically, the latter using the…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Jonathan Frazer , Andrew R Liddle

In the standard inflationary scenario with inflaton potential $V(\Phi)=M^4-{1\over4}\lambda\Phi^4$, the resulting density perturbations $\delta\rho/\rho$ are proportional to $\lambda^{1/2}$. Upper bounds on $\delta\rho/\rho$ require…

Astrophysics · Physics 2009-10-22 Toby Falk , Raghavan Rangarajan , Mark Srednicki

A smooth inflaton potential is generally assumed when calculating the primordial power spectrum, implicitly assuming that a very small oscillation in the inflaton potential creates a negligible change in the predicted halo mass function. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Luiz Felippe S. Rodrigues , Reuven Opher