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We analyse the dynamics of spinodal decomposition in inflationary cosmology using the closed time path formalism of out of equilibrium quantum field theory combined with the non-perturbative Hartree approximation. In addition to a general…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. Cormier , R. Holman

Slow-roll of the inflaton (inflationary field) defines the standard dynamics of the inflationary epoch. However, the inflaton deviates from slow-roll when it encounters an extremely flat region in the inflationary potential, and enters a…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Aarav Shah

Inflation creates both scalar (density) and tensor (gravity wave) metric perturbations. We find that the tensor mode contribution to the CMB anisotropy on large-angular scales can only exceed that of the scalar mode in models where the…

Astrophysics · Physics 2009-09-15 R. L. Davis , H. M. Hodges , G. F. Smoot , P. J. Steinhardt , M. S. Turner

Recently, we have shown that scalar spectra with lower power on large scales and certain other features naturally occur in {\it punctuated inflation}, i.e. the scenario wherein a brief period of rapid roll is sandwiched between two stages…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Rajeev Kumar Jain , Pravabati Chingangbam , L. Sriramkumar , Tarun Souradeep

Cosmologists have embraced a particular ad hoc formula for the primordial power spectrum from inflation for universes with $\Omega_0 < 1$. However, the so-called ``Open Inflation'' models, which are attracting renewed interest in the…

High Energy Physics - Theory · Physics 2007-05-23 Michael Barnard , Andreas Albrecht

We consider the possibility of suppressing superhorizon curvature perturbations after the end of the ordinary slow-roll inflationary stage. This is the opposite of the curvaton limit. We assume that large curvature perturbations are created…

High Energy Physics - Phenomenology · Physics 2009-11-11 Martin S. Sloth

Adams et al. (1997b) have noted that according to our current understanding of the unification of fundamental interactions, there should have been phase transitions associated with spontaneous symmetry breaking {\em during} the inflationary…

Astrophysics · Physics 2008-11-26 Jose Barriga , Enrique Gaztanaga , Mario Santos , Subir Sarkar

We provide a compact and unified treatment of power spectrum observables for the effective field theory (EFT) of inflation with the complete set of operators that lead to second-order equations of motion in metric perturbations in both…

High Energy Physics - Theory · Physics 2019-01-15 Hayato Motohashi , Wayne Hu

Warm inflation includes inflaton interactions with other fields throughout the inflationary epoch instead of confining such interactions to a distinct reheating era. Previous investigations have shown that, when certain constraints on the…

High Energy Physics - Phenomenology · Physics 2016-01-06 Mar Bastero-Gil , Arjun Berera , Nico Kronberg

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

If the universe had a large curvature before inflation there is a deviation from the scale invariant perturbations of the inflaton at the beginning of inflation. This may have some effect on the CMB anisotropy at large angular scales. We…

Astrophysics · Physics 2008-11-26 Eduard Masso , Subhendra Mohanty , Akhilesh Nautiyal , Gabriel Zsembinszki

We study slow-roll inflation on a three-brane in a five-dimensional bulk where the effects of energy loss from the brane due to graviton emission is included in a self-consistent manner. We explicitly derive the form of the energy loss term…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-07 Ashok Thillaisundaram

We investigate a single field model in the context of the constant-roll inflation in which inflaton moves down to the minimum point of the potential with a constant rate of rolling. We use a quintessential inflationary model obtained by a…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-23 Mehdi Shokri , Jafar Sadeghi , Saeed Noori Gashti

We show that deviations of the quantum state of the inflaton from the thermal vacuum of inflation may leave an imprint in the CMB anisotropies. The quantum dynamics of the inflaton in such a state produces corrections to the inflationary…

High Energy Physics - Theory · Physics 2009-11-10 Nemanja Kaloper , Manoj Kaplinghat

Models of axion inflation are particularly interesting since they provide a natural justification for the flatness of the potential over a super-Planckian distance, namely the approximate shift-symmetry of the inflaton. In addition, most of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 P. Daniel Meerburg , Enrico Pajer

We present here the effective theory of inflation `a la Ginsburg-Landau in which the inflaton potential is a polynomial. The slow-roll expansion becomes a systematic 1/N expansion where N ~ 60. The spectral index and the ratio of…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-24 H. J. de Vega

In multiple inflation scenario having two inflations with an intermediate matter-dominated phase, the power spectrum is estimated to be enhanced on scales smaller than the horizon size at the beginning of the second inflation, $k > k_{\rm…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-16 Gimin Bae , Sungjae Bae , Seungho Choe , Seo Hyun Lee , Jungwon Lim , Heeseung Zoe

We investigate to what extent future microwave background experiments might be able to detect a suppression of fluctuation power on large scales in flat and open universe models. Such suppression would arise if fluctuations are generated by…

Astrophysics · Physics 2008-11-26 Arjun Berera , Alan F. Heavens

We have proposed a new class of inflationary scenarios in which the first stage of expansion is driven by "old" false vacuum inflation. This ends by nucleation of a bubble, which then further inflates. Unlike the standard slow-roll…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gia Dvali , Shamit Kachru

During single clock inflation, hidden fields (i.e. fields coupled to the inflaton only gravitationally) in their adiabatic vacua can ordinarily only affect observables through virtual effects. After renormalizing background quantities…

General Relativity and Quantum Cosmology · Physics 2019-01-30 Adrian del Rio , Ruth Durrer , Subodh P. Patil
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