English
Related papers

Related papers: What Planck does not tell us about inflation

200 papers

Recently multi-field inflation models that can produce large scalar fluctuations on small scales have drawn a lot of attention, primarily because they could lead to primordial black hole production and generation of large second-order…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-21 Laura Iacconi , David J. Mulryne

We adopt the double field natural inflation model motivated by the non-perturbative effects of supergravity and superstring theory to do the slow roll analysis. We show that when the parameters are suitably chosen, there exist ranges of…

General Relativity and Quantum Cosmology · Physics 2019-04-12 Ping Kwan Man Ellgan

We study models of inflation with two scalar fields and non-canonical kinetic terms, focusing on the case in which the curvature and isocurvature perturbations are strongly coupled to each other. In the regime where a heavy mode can be…

High Energy Physics - Theory · Physics 2011-03-10 Sera Cremonini , Zygmunt Lalak , Krzysztof Turzynski

Inflation models are compared with observation on the assumption that the curvature perturbation is generated from the vacuum fluctuation of the inflaton field. The focus is on single-field models with canonical kinetic terms, classified as…

High Energy Physics - Theory · Physics 2009-04-22 D H Lyth

Using the \delta N formalism we consider the non-linear curvature perturbation in multi-field models of inflation with non-minimal coupling. In particular, we focus on the relation between the \delta N formalism as applied in the…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-25 Jonathan White , Masato Minamitsuji , Misao Sasaki

Non-abelian gauge field inflation is studied in the context of warm inflation scenario. We introduce this scenario as a mechanism that gives an end for gauge-flation model. Slow-roll parameters and perturbation parameters are presented for…

General Relativity and Quantum Cosmology · Physics 2015-06-17 M. R. Setare , V. Kamali

Modular inflation is the restriction to two fields of automorphic inflation, a general group based framework for multifield scalar field theories with curved target spaces, which can be parametrized by the comoving curvature perturbation…

High Energy Physics - Theory · Physics 2019-01-01 Rolf Schimmrigk

We present two families of multi-field potentials that support inflation while satisfying the refined de Sitter and the distance swampland conjectures. Both families feature Planck-compatible phenomenology. The first is a helix-type…

High Energy Physics - Theory · Physics 2020-04-29 Vikas Aragam , Sonia Paban , Robert Rosati

Coupled, multi-field models of inflation can provide several attractive features unavailable in the case of a single inflaton field. These models have a rich dynamical structure resulting from the interaction of the fields and their…

High Energy Physics - Phenomenology · Physics 2009-11-07 Daniel Cormier , Katrin Heitmann , Anupam Mazumdar

We consider single field chaotic inflationary models plus a cosine modulation term, as in axion monodromy models, and augment it by a light scalar field with similar cosine coupling. We show the power spectrum of curvature perturbations of…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-13 Ali Akbar Abolhasani , M. M. Sheikh-Jabbari

Models of cosmic inflation suggest that our universe underwent an early phase of accelerated expansion, driven by the dynamics of one or more scalar fields. Inflationary models make specific, quantitative predictions for several observable…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-10 David I. Kaiser

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

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 revisit the status of hybrid inflation in the light of Planck and recent BICEP2 results, taking care of possible transient violations of the slow-roll conditions as the field passes from the large field to the vacuum dominated phase. The…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-05 Sebastien Clesse , Jeremy Rekier

Motivated by the result of Planck+BICEP/Keck recently released, we investigate the consistency of the multi-field inflation models in terms of the spectral index $n_s$ and the tensor-to-scalar ratio $r$. In this study, we focus on…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-03 Yukiyoshi Morishita , Tomo Takahashi , Shuichiro Yokoyama

In this work, we examine cosmological constraints on models of composite inflation based on the slow-roll approximation by using the recent Planck measurement. We compare the spectral index of curvature perturbation (and its running) and…

High Energy Physics - Phenomenology · Physics 2016-06-30 Phongpichit Channuie

We propose a new broad class of multi-field non-canonical inflationary models as an extension of multi-field conformal cosmological attractors. This also generalizes the recently discovered class of non-canonical conformal attractors for…

High Energy Physics - Theory · Physics 2020-03-17 Tony Pinhero , Supratik Pal

The evolution of the curvature perturbation after multi-field inflation is studied in the light of the curvaton mechanism. Past numerical studies show that many-field inflation causes significant evolution of the curvature perturbation…

High Energy Physics - Phenomenology · Physics 2015-06-15 Seishi Enomoto , Tomohiro Matsuda

Theories where the Planck scale is dynamically generated from dimensionless interactions provide predictive inflationary potentials and super-Planckian field variations. We first study the minimal single-field realisation in the low-energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-28 Kristjan Kannike , Gert Hütsi , Liberato Pizza , Antonio Racioppi , Martti Raidal , Alberto Salvio , Alessandro Strumia

We investigate whether the predictions of single-field models of inflation are robust under the introduction of additional scalar degrees of freedom, and whether these extra fields change the potentials for which the data show the strongest…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-26 Vincent Vennin , Kazuya Koyama , David Wands
‹ Prev 1 3 4 5 6 7 10 Next ›