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We study the preheating process in a model of DBI inflation with a DBI-type inflaton coupling to a canonical entropy field. At the end of inflation, the inflaton field oscillates around its vacuum which can arise from an infrared cutoff…

High Energy Physics - Theory · Physics 2013-08-12 Jun Zhang , Yifu Cai , Yun-Song Piao

We investigate the construction of approximated exchange-correlation functionals by interpolating locally along the adiabatic connection between the weak- and the strong-coupling regimes, focussing on the effect of using approximate…

Chemical Physics · Physics 2017-04-05 Stefan Vuckovic , Lucas O. Wagner , Andrew M. Teale , Paola Gori-Giorgi

We examine the covariant properties of generalized models of two-field inflation, with non-canonical kinetic terms and a possibly non-trivial field metric. We demonstrate that kinetic-term derivatives and covariant field derivatives do…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-28 Eleftheria Tzavara , Shuntaro Mizuno , Bartjan van Tent

The sensitivity of inflationary spectra to initial conditions is addressed in the context of a phenomenological model that breaks Lorentz invariance by dissipative effects above some threshold energy $\Lambda$. These effects are obtained…

High Energy Physics - Phenomenology · Physics 2008-11-26 Julian Adamek , David Campo , Jens C. Niemeyer , Renaud Parentani

In loop quantum gravity, modifications to the geometrical density cause a self-interacting scalar field to accelerate away from a minimum of its potential. In principle, this mechanism can generate the conditions that subsequently lead to…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Martin Bojowald , James E. Lidsey , David J. Mulryne , Parampreet Singh , Reza Tavakol

We study the radiative corrections of the noncommutative QED at the one-loop level. A correction of the magnetic dipole moment due to the noncommutativity are evaluated. As in the ordinary QED, IR divergence is shown to vanish when we…

High Energy Physics - Theory · Physics 2007-05-23 Ki Boum Eom , Sung-Shig Kang , Bum-Hoon Lee , Chanyong Park

We explore the consequences of loop quantum cosmology (inverse-volume corrections) in the spectrum of the gravitational waves using the method of the Bogoliubov coefficients. These corrections are taken into account at the background level…

General Relativity and Quantum Cosmology · Physics 2014-01-22 Joao Morais , Mariam Bouhmadi-Lopez , Alfredo B. Henriques

It is well understood that spatial non-commutativity, if indeed realized in nature, is a phenomenon whose effects are not just felt at energy scales comparable to the non-commutativity scale. Loop effects can transmit signatures of any…

High Energy Physics - Theory · Physics 2009-11-05 Gonzalo A. Palma , Subodh P. Patil

While moving down the potential on its classical slow roll trajectory, the inflaton field is subject to quantum jumps, which take it up or down the potential at random. In "stochastic inflation", the impact of these quantum jumps is modeled…

High Energy Physics - Theory · Physics 2015-05-20 Larissa Lorenz

We compute all of the one-loop corrections that are enhanced, $O(\lambda_i \lambda_j / 16 \pi^2)$, in the limit $s \gg |\lambda_i | v^2 \gg M_{W}^2$, $s \gg m_{12}^2$ to all the $2 \to 2$ longitudinal vector boson and Higgs boson scattering…

High Energy Physics - Phenomenology · Physics 2016-06-29 Benjamín Grinstein , Christopher W. Murphy , Patipan Uttayarat

In this paper, we have constructed quantum effective potentials and used them to study slow-roll inflationary cosmology. We derived the generalised RG equation for the effective potential in the leading logarithmic approximation and applied…

High Energy Physics - Theory · Physics 2023-08-17 D. I. Kazakov , R. M. Iakhibbaev , D. M. Tolkachev

We study DBI spinflation models with angular potentials that are derived in string theory. We analyse the background dynamics with different parameter sets and study the impact of changing each parameter on inflationary dynamics. It is…

High Energy Physics - Theory · Physics 2014-10-22 Taichi Kidani , Kazuya Koyama

We consider the Einstein equations within the DBI scenario for a spatially flat Friedmann-Robertson-Walker (FRW) spacetime without a cosmological constant. We derive the inflationary scenario by applying the symmetry transformations which…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 L. P. Chimento , R. Lazkoz , M. G. Richarte

Lattice QCD studies of hadron-hadron interactions are performed by computing the energy levels of the system in a finite box. The shifts in energy levels proportional to inverse powers of the volume are related to scattering parameters in a…

High Energy Physics - Lattice · Physics 2014-11-17 Paulo F. Bedaque , Ikuro Sato , Andre Walker-Loud

In this paper we study the entropy perturbations in N-flation by using the $\d\ma{N}$ formalism. We calculate the entropy corrections to the power spectrum of the overall curvature perturbation $P_{\z}$. We obtain an analytic form of the…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-14 Rong-Gen Cai , Bin Hu , Yun-Song Piao

Loops of inflationary gravitons are known to induce large temporal and spatial logarithms which can cause perturbation theory to break down. Nonlinear sigma models possess the same kind of derivative interactions and induce the same sorts…

General Relativity and Quantum Cosmology · Physics 2023-09-11 C. Litos , R. P. Woodard , B. Yesilyurt

We study the evolution of linear density perturbations in the context of interacting scalar field-dark matter cosmologies, where the presence of the coupling acts as a stabilization mechanism for the runaway behavior of the scalar…

Astrophysics · Physics 2008-11-26 Pier Stefano Corasaniti

In this paper we study a new class of inflation models which generalize the Dirac-Born-Infeld (DBI) action with the addition of a nonminimal kinetic coupling (NKC) term. We dubbed this model as the {\it new DBI inflation model}. The NKC…

High Energy Physics - Theory · Physics 2016-08-04 Taotao Qiu

Phenomenological studies of cosmological collider physics in recent years have identified many 1-loop inflation correlators as leading channels for discovering heavy new particles around or above the inflation scale. However, complete…

High Energy Physics - Theory · Physics 2023-05-10 Zhong-Zhi Xianyu , Hongyu Zhang

We study the asymmetric primordial fluctuations in a model of inflation in which translational invariance is broken by a domain wall. We calculate the corrections to the power spectrum of curvature perturbations; they are anisotropic and…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-02 Sadra Jazayeri , Yashar Akrami , Hassan Firouzjahi , Adam R. Solomon , Yi Wang
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