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Related papers: What Planck does not tell us about inflation

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We consider small-field models which invoke the usual framework for the effective field theory, and large-field models which go beyond that. Present and future possibilities for discriminating between the models are assessed, on the…

Astrophysics · Physics 2015-06-24 Laila Alabidi , David Lyth

We study inflation in models with many interacting fields subject to randomly generated scalar potentials. We use methods from non-equilibrium random matrix theory to construct the potentials and an adaption of the 'transport method' to…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 Mafalda Dias , Jonathan Frazer , M. C. David Marsh

Bayesian inference techniques are used to investigate situations where an additional light scalar field is present during inflation and reheating. This includes (but is not limited to) curvaton-type models. We design a numerical pipeline…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-13 Vincent Vennin , Kazuya Koyama , David Wands

We study the two-field warm inflation models with a double quadratic potential and a linear temperature dependent dissipative coefficient. We derived the evolution equation of all kinds of perturbations without assuming slow-roll…

General Relativity and Quantum Cosmology · Physics 2019-05-23 Yang-yang Wang , Xiao-Min Zhang , Jian-Yang Zhu

After the release of the PLANCK data, it is evident that inflationary paradigm has stood the test of time. Even though, it is difficult to realise inflationary paradigm in a particle physics model as the present observations have ruled out…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-29 Suratna Das , Girish Kumar Chakravarty , Gaetano Lambiase , Subhendra Mohanty

We study the bispectrum of the curvature perturbation on uniform energy density hypersurfaces in models of inflation with two scalar fields evolving simultaneously. In the case of a separable potential, it is possible to compute the…

Astrophysics · Physics 2009-11-11 Filippo Vernizzi , David Wands

We derive semi-analytic formulae for the local bispectrum and trispectrum in general two-field inflation and provide a simple geometric recipe for building observationally allowed models with observable non-Gaussianity. We use the \delta N…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Courtney M. Peterson , Max Tegmark

The observational signatures of multi-field inflation will generally evolve as the Universe reheats. We introduce a general analytic formalism for tracking this evolution through perturbative reheating, applicable to two field models with…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-28 Joseph Elliston , Stefano Orani , David J. Mulryne

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

We investigate the inflationary universe in a theory where two scalar fields non-minimally coupling to the scalar curvature and an extra $R^2$ term exist and the conformal invariance is broken. In particular, the slow-roll inflation is…

High Energy Physics - Theory · Physics 2016-03-01 Kazuharu Bamba

Multifield models of inflation with nonminimal couplings are in excellent agreement with the recent results from {\it Planck}. Across a broad range of couplings and initial conditions, such models evolve along an effectively single-field…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-08 David I. Kaiser , Evangelos I. Sfakianakis

Until recently our knowledge of the primordial curvature perturbation was relatively modest. Ever since COBE delivered its map of data we know the scalar spectrum of primordial perturbations is approximately flat, with the power being only…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-24 Raquel H. Ribeiro

The latest results from PLANCK impose strong constraints on features in the spectrum of the curvature perturbations from inflation. We analyse the possibility of particle production induced by sharp turns of the trajectory in field space in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Maciej Konieczka , Raquel H. Ribeiro , Krzysztof Turzynski

We present a two-field inflation model where inflaton field has a non-canonical kinetic term due to the presence of a dilaton field. It is a two-parameter generalization of one-parameter Brans-Dicke gravity in the Einstein frame. We show…

High Energy Physics - Phenomenology · Physics 2016-08-03 Girish Kumar Chakravarty , Suratna Das , Gaetano Lambiase , Subhendra Mohanty

Recent studies of inflation with multiple scalar fields have highlighted the importance of non-canonical kinetic terms in novel types of inflationary solutions. This motivates a thorough analysis of non-Gaussianities in this context, which…

High Energy Physics - Theory · Physics 2020-02-11 Sebastian Garcia-Saenz , Lucas Pinol , Sébastien Renaux-Petel

We consider inflation in the system containing a Ricci scalar squared term and a canonical scalar field with quadratic mass term. In the Einstein frame this model takes the form of a two-field inflation model with a curved field space, and…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-01 Taro Mori , Kazunori Kohri , Jonathan White

In the standard slow-roll inflationary cosmology, quantum fluctuations in a single field, the inflaton, generate approximately Gaussian primordial density perturbations. At present, the bispectrum and trispectrum of the density…

High Energy Physics - Phenomenology · Physics 2010-08-03 Kevin T. Engel , Keith S. M. Lee , Mark B. Wise

We report first study of complex field inflation. Although understood as a specific two-field inflation, a complex field inflation is able to make more robust model predictions on primordial curvature perturbation. Explicitly we discuss the…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-22 Ruopeng Zhang , Sibo Zheng

These lecture notes have been written for a short introductory course on the status of inflation after Planck and BICEP2, given at the Xth Modave School of Mathematical Physics. The first objective is to give an overview of the theory of…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-05 Sebastien Clesse

Heavy scalar fields can undergo an instability during inflation as a result of their kinetic couplings with the inflaton. This is known as the geometrical destabilization of inflation, as it relies on the effect of the negative curvature of…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-07 Sebastian Garcia-Saenz , Sébastien Renaux-Petel , John Ronayne
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