Towards the theory of reheating after inflation
Reads0
Chats0
TLDR
In this paper, the authors investigated a simple model of a massive inflaton field coupled to another scalar field with the interaction term, and developed the theory of preheating taking into account the expansion of the universe and back reaction of produced particles, including the effects of rescattering.Abstract:
Reheating after inflation occurs due to particle production by the oscillating inflaton field. In this paper we briefly describe the perturbative approach to reheating, and then concentrate on effects beyond the perturbation theory. They are related to the stage of parametric resonance, which we call preheating. It may occur in an expanding universe if the initial amplitude of oscillations of the inflaton field is large enough. We investigate a simple model of a massive inflaton field $\ensuremath{\varphi}$ coupled to another scalar field $\ensuremath{\chi}$ with the interaction term ${g}^{2}{\ensuremath{\varphi}}^{2}{\ensuremath{\chi}}^{2}$. Parametric resonance in this model is very broad. It occurs in a very unusual stochastic manner, which is quite different from parametric resonance in the case when the expansion of the universe is neglected. Quantum fields interacting with the oscillating inflaton field experience a series of kicks which, because of the rapid expansion of the universe, occur with phases uncorrelated to each other. Despite the stochastic nature of the process, it leads to exponential growth of fluctuations of the field $\ensuremath{\chi}$. We call this process stochastic resonance. We develop the theory of preheating taking into account the expansion of the universe and back reaction of produced particles, including the effects of rescattering. This investigation extends our previous study of reheating after inflation. We show that the contribution of the produced particles to the effective potential $V(\ensuremath{\varphi})$ is proportional not to ${\ensuremath{\varphi}}^{2}$, as is usually the case, but to $|\ensuremath{\varphi}|$. The process of preheating can be divided into several distinct stages. In the first stage the back reaction of created particles is not important. In the second stage back reaction increases the frequency of oscillations of the inflaton field, which makes the process even more efficient than before. Then the effects related to scattering of $\ensuremath{\chi}$ particles on the oscillating inflaton field terminate the resonance. We calculate the number density of particles ${n}_{\ensuremath{\chi}}$ produced during preheating and their quantum fluctuations $〈{\ensuremath{\chi}}^{2}〉$ with all back reaction effects taken into account. This allows us to find the range of masses and coupling constants for which one can have efficient preheating. In particular, under certain conditions this process may produce particles with a mass much greater than the mass of the inflaton field.read more
Citations
More filters
Journal ArticleDOI
Planck 2015 results. XX. Constraints on inflation
Peter A. R. Ade,Nabila Aghanim,Monique Arnaud,Frederico Arroja,M. Ashdown,J. Aumont,Carlo Baccigalupi,Mario Ballardini,A. J. Banday,R. B. Barreiro,Nicola Bartolo,E. Battaner,K. Benabed,Alain Benoit,A. Benoit-Lévy,J.-P. Bernard,Marco Bersanelli,P. Bielewicz,J. J. Bock,Anna Bonaldi,Laura Bonavera,J. R. Bond,Julian Borrill,François R. Bouchet,F. Boulanger,M. Bucher,Carlo Burigana,R. C. Butler,Erminia Calabrese,Jean-François Cardoso,A. Catalano,Anthony Challinor,A. Chamballu,R.-R. Chary,H. C. Chiang,P. R. Christensen,Sarah E. Church,David L. Clements,S. Colombi,L. P. L. Colombo,C. Combet,D. Contreras,F. Couchot,A. Coulais,B. P. Crill,A. Curto,F. Cuttaia,Luigi Danese,R. D. Davies,R. J. Davis,P. de Bernardis,A. de Rosa,G. de Zotti,Jacques Delabrouille,F.-X. Désert,Jose M. Diego,H. Dole,S. Donzelli,Olivier Doré,Marian Douspis,A. Ducout,X. Dupac,George Efstathiou,F. Elsner,Torsten A. Ensslin,H. K. Eriksen,James R. Fergusson,Fabio Finelli,Olivier Forni,M. Frailis,Aurelien A. Fraisse,E. Franceschi,A. Frejsel,Andrei V. Frolov,S. Galeotta,Silvia Galli,K. Ganga,C. Gauthier,M. Giard,Y. Giraud-Héraud,E. Gjerløw,J. González-Nuevo,Krzysztof M. Gorski,Serge Gratton,A. Gregorio,Alessandro Gruppuso,Jon E. Gudmundsson,Jan Hamann,Will Handley,F. K. Hansen,Duncan Hanson,D. L. Harrison,Sophie Henrot-Versille,C. Hernández-Monteagudo,D. Herranz,S. R. Hildebrandt,E. Hivon,Michael P. Hobson,W. A. Holmes +98 more
TL;DR: In this article, the authors report on the implications for cosmic inflation of the 2018 Release of the Planck CMB anisotropy measurements, which are fully consistent with the two previous Planck cosmological releases, but have smaller uncertainties thanks to improvements in the characterization of polarization at low and high multipoles.
Journal ArticleDOI
f(R) theories
TL;DR: Various applications of f(R) theories to cosmology and gravity — such as inflation, dark energy, local gravity constraints, cosmological perturbations, and spherically symmetric solutions in weak and strong gravitational backgrounds are reviewed.
Journal ArticleDOI
The Case for a Positive Cosmological Λ-Term
TL;DR: In this article, the authors review both observational and theoretical aspects of a small cosmological Λ-term and discuss the current observational situation focusing on cosmology tests of Λ including the age of the universe, high redshift supernovae, gravitational lensing, galaxy clustering and the cosmic microwave background.
Journal ArticleDOI
Modified gravity theories on a nutshell: Inflation, bounce and late-time evolution
TL;DR: In this paper, the authors systematically review some standard issues and also the latest developments of modified gravity in cosmology, emphasizing on inflation, bouncing cosmology and late-time acceleration era.
Journal ArticleDOI
Particle physics models of inflation and the cosmological density perturbation
David H. Lyth,Antonio Riotto +1 more
TL;DR: A review of particle-theory models of inflation, and their predictions for the primordial density perturbation that is thought to be the origin of structure in the Universe is given in this paper.
References
More filters
Journal ArticleDOI
Handbook of Mathematical Functions
Book
An Introduction to Quantum Field Theory
TL;DR: Feynman Diagrams and Quantum Electrodynamics as discussed by the authors have been used to describe the Parton Model of Hadron Structure, the Klein-Gordon Field, and the Dirac Field.
Particle Physics and Inflationary Cosmology
TL;DR: A monograph on inflationary cosmology and cosmological phase transitions is presented in this article, which investigates modern cosmology's relationship to elementary particle physics and includes a non-technical discussion of the theory for those unfamiliar with the theory.
Book
Particle Physics and Inflationary Cosmology
TL;DR: A monograph on inflationary cosmology and cosmological phase transitions is presented in this paper, which investigates modern cosmology's relationship to elementary particle physics and includes a non-technical discussion of the theory for those unfamiliar with the theory.