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Related papers: Constraints on Pre-inflation Fluctuations in a Nea…

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We study reheating in $\alpha$-attractor models of inflation in which the inflaton couples to other scalars or fermions. We show that the parameter space contains viable regions in which the inflaton couplings to radiation can be determined…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 Marco Drewes , Jin U Kang , Ui Ri Mun

The standard inflationary model presents a simple scenario within which the homogeneity, isotropy and flatness of the universe appear as natural outcomes and, in addition, fluctuations in the energy density are originated during the…

Astrophysics · Physics 2023-03-08 E. Martinez-Gonzalez , P. Vielva

We study the problem of initial conditions for slow-roll inflation along a plateau-like scalar potential within the framework of fluctuation-dissipation dynamics. We consider, in particular, that inflation was preceded by a…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-09 Mar Bastero-Gil , Arjun Berera , Robert Brandenberger , Ian G. Moss , Rudnei O. Ramos , Joao G. Rosa

We study the perspectives to extract information about the microphysical parameters that governed the reheating process after cosmic inflation from CMB data. We identify conditions under which the inflaton coupling to other fields can be…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-30 Marco Drewes

Since inflationary perturbations must generically couple to all degrees of freedom present in the early Universe, it is more realistic to view these fluctuations as an open quantum system interacting with an environment. Then, on very…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-10 Jerome Martin , Vincent Vennin

Whereas preheating after chaotic and hybrid inflation models has been abundantly studied in the literature, preheating in small field inflation models, where the curvature of the inflaton potential is negative during inflation, remains less…

High Energy Physics - Theory · Physics 2015-03-17 Philippe Brax , Jean-Francois Dufaux , Sophie Mariadassou

We investigate inflationary scenarios driven by a class of potentials which are similar in form to those that arise in certain minimal supersymmetric extensions of the standard model. We find that these potentials allow a brief period of…

Warm inflation has normalized two ideas in cosmology, that in the early universe the initial primordial density perturbations generally could be of classical rather than quantum origin and that during inflation, particle production from…

High Energy Physics - Phenomenology · Physics 2023-06-23 Arjun Berera

Inflation can occur near a point of inflection in the potential of flat directions of the Minimal Supersymmetric Standard Model. In this paper we elaborate on the complementarity between the bounds from Cosmic Microwave Background…

High Energy Physics - Phenomenology · Physics 2014-11-20 Rouzbeh Allahverdi , Bhaskar Dutta , Yudi Santoso

We investigate if the observed small and nearly scale-invariant primordial cosmic perturbation, i.e. the perturbation amplitude $P_\zeta\sim10^{-9}$ and the spectral index $n_s \simeq 0.965$, is typical in the landscape of vacua after…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Chien-I Chiang , Keisuke Harigaya

If the spatial curvature of the universe is positive, then the curvature term will always dominate at early enough times in a slow-rolling inflationary epoch. This enhances inflationary effects and hence puts limits on the possible number…

General Relativity and Quantum Cosmology · Physics 2015-06-25 G. F. R. Ellis , W. Stoeger , P. McEwan , P. Dunsby

We consider a double-inflationary model with two massive scalar fields interacting only gravitationally in the context of a flat cold dark matter (CDM) Universe. The cosmic microwave background (CMB) temperature anisotropies produced in…

Astrophysics · Physics 2009-10-30 Julien Lesgourgues , David Polarski

We discuss structure formation in models with a spectator field in small-field inflation which accommodate a secondary period of inflation. In such models, subgalactic scale primordial fluctuations can be much suppressed in comparison to…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 Kari Enqvist , Till Sawala , Tomo Takahashi

Using an approximate likelihood method adapted to band--power estimates, we analyze the ensemble of first generation cosmic microwave background anisotropy experiments to deduce constraints over a six--dimensional parameter space describing…

Astrophysics · Physics 2011-05-23 M. Le Dour , M. Douspis , J. G. Bartlett , A. Blanchard

We confront the warm inflation observational predictions directly with the latest CMB data. We focus on a linear temperature (T) dissipative coefficient combined with the simplest model of inflation, a quartic chaotic potential. Although…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-06 Mar Bastero-Gil , Sukannya Bhattacharya , Koushik Dutta , Mayukh Raj Gangopadhyay

Recent results from cosmic microwave background (CMB) experiments verify several of the predictions of inflation, while ruling out a number of alternative structure-formation scenarios. Given the successes of the theory, the obvious next…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski

We consider string and supergravity motivated scenarios in which moduli fields dominate the energy density of the Universe in a post-inflationary epoch. For the case of a single light modulus it has been shown that considering the evolution…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-16 Rajesh Goswami , Urjit A. Yajnik

I present a pedagogical review of inflation and the cosmic microwave background. I describe how a short period of accelerated expansion can replace the special initial conditions of the standard big bang model. I also describe the…

Astrophysics · Physics 2017-08-23 Charles H. Lineweaver

Cosmological $\alpha$-attractors stand out as particularly compelling models to describe inflation in the very early universe, naturally meeting tight observational bounds from cosmic microwave background (CMB) experiments. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-22 Laura Iacconi , Hooshyar Assadullahi , Matteo Fasiello , David Wands

We analyze the limits on resonant particle production during inflation based upon the power spectrum of fluctuations in matter and the cosmic microwave background. We show that such a model is consistent with features observed in the matter…

Astrophysics · Physics 2009-11-10 G. J. Mathews , D. J. H. Chung , K. Ichiki , T. Kajino , M. Orito
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