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We study the statistical descriptors for some cosmological inflationary models that allow us to get large levels of non-gaussianity and violations of statistical isotropy. Basically, we study two different class of models: a model that…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-05 Cesar A. Valenzuela-Toledo

We demonstrate that in the presence of a light scalar spectator field, vacuum transitions taking place during inflation can produce large, potentially detectable non-Gaussian signatures in the primordial curvature perturbation. Such…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-27 Björn Garbrecht , Pulkit S. Ghoderao , Arttu Rajantie

The shift-symmetric coupling of a pseudo-scalar particle driving inflation to gauge fields provides a unique way of probing cosmic inflation. We show for an SU(2) gauge group how a classical isotropic background gauge field develops from…

High Energy Physics - Phenomenology · Physics 2019-04-24 Valerie Domcke , Ben Mares , Francesco Muia , Mauro Pieroni

The asymmetrically forced, damped Duffing oscillator is introduced as a prototype model for analyzing the homoclinic tangle of symmetric dissipative systems with \textit{symmetry breaking} disturbances. Even a slight fixed asymmetry in the…

Dynamical Systems · Mathematics 2016-09-06 Anna Litvak Hinenzon , Vered Rom-Kedar

In the simplest model of open inflation there are two inflaton fields decoupled from each other. One of them, the tunneling field, produces a first stage of inflation which prepares the ground for the nucleation of a highly symmetric…

Astrophysics · Physics 2009-10-30 Jaume Garriga , V. F. Mukhanov

We explore a fluid description of the inflationary universe. In particular, we investigate a fluid model in which the equation of state (EoS) for a fluid includes bulk viscosity. We find that the three observables of inflationary cosmology:…

General Relativity and Quantum Cosmology · Physics 2016-02-17 Kazuharu Bamba , Sergei D. Odintsov

We consider a supersymmetric grand unified model which leads to hybrid inflation and solves the strong CP and mu problems via a Peccei-Quinn symmetry, with the Peccei-Quinn field acting as a curvaton generating together with the inflaton…

High Energy Physics - Phenomenology · Physics 2009-11-11 George Lazarides

We use high resolution direct numerical simulations to study the anisotropic contents of a turbulent, statistically homogeneous flow with random transitions among multiple energy containing states. We decompose the velocity correlation…

Fluid Dynamics · Physics 2017-07-05 Kartik P. Iyer , Fabio Bonaccorso , Luca Biferale , Federico Toschi

In binary superfluid counterflow systems, vortex nucleation arises as a consequence of hydrodynamic instabilities when the coupling coefficient and counterflow velocity exceed the critical value. When dealing with two identical components,…

Quantum Gases · Physics 2024-01-30 Wei-can Yang , Makoto Tsubota , Hua-bi Zeng

We analyze the dynamics and observational predictions of supersymmetric hybrid inflation in the warm regime, where dissipative effects are mediated by the waterfall fields and their subsequent decay into light degrees of freedom. This…

High Energy Physics - Phenomenology · Physics 2015-06-18 Mar Bastero-Gil , Arjun Berera , Thomas P. Metcalf , Joao G. Rosa

In the standard slow-roll inflationary cosmology, quantum fluctuations in a single field, the inflaton, generate approximately Gaussian primordial density perturbations. At present, the bispectrum and trispectrum of the density…

High Energy Physics - Phenomenology · Physics 2010-08-03 Kevin T. Engel , Keith S. M. Lee , Mark B. Wise

In this Letter, we use a model fluid mechanics experiment to elucidate the impact of curvature heterogeneities on two-dimensional fields deriving from harmonic potential functions. This result is directly relevant to explain the smooth…

Soft Condensed Matter · Physics 2023-09-08 Stéphane Guillet , Benjamin Guiselin , Mariem Boughzala , Vassili Desages , Denis Bartolo

We study the imprints of anisotropic inflation on the CMB temperature fluctuations and polarizations. The statistical anisotropy stems not only from the direction dependence of curvature and tensor perturbations, but also from the cross…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-23 Masa-aki Watanabe , Sugumi Kanno , Jiro Soda

We revisit the quantum theory of a massive, minimally coupled scalar field, propagating on the Planck-era isotropic cosmological quantum spacetime which transitions to a classical spacetime in later times. The quantum effects modify the…

General Relativity and Quantum Cosmology · Physics 2020-03-06 Saeed Rastgoo , Yaser Tavakoli , Julio C. Fabris

We consider models of chaotic inflation driven by the real parts of a conjugate pair of Higgs superfields involved in the spontaneous breaking of a grand unification symmetry at a scale assuming its supersymmetric value. Employing quadratic…

High Energy Physics - Phenomenology · Physics 2018-01-30 C. Pallis

The primordial bispectrum has been considered in the past decade as a powerful probe of the physical processes taking place in the early Universe. Within the inflationary paradigm, the properties of the bispectrum are one of the keys that…

General Relativity and Quantum Cosmology · Physics 2015-03-09 Gabriel Leon , Daniel Sudarsky

It has recently been suggested that a strongly coupled phase of inflation may be described holographically in terms of a weakly coupled quantum field theory (QFT). Here, we explore the possibility that the wave function of an inflationary…

High Energy Physics - Theory · Physics 2015-06-15 Jaume Garriga , Yuko Urakawa

The verification of whether small-scale turbulence is isotropic remains a grand challenge. The difficulty arises because the presence of small-scale anisotropy is tied to the dissipation tensor, whose components require the full…

Fluid Dynamics · Physics 2024-05-03 Subharthi Chowdhuri , Tirtha Banerjee

Realistic models of particle physics include many scalar fields. These fields generically have nonminimal couplings to the Ricci curvature scalar, either as part of a generalized Einstein theory or as necessary counterterms for…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-27 David I. Kaiser , Audrey T. Todhunter

Out-of-equilibrium, non-perturbative, quantum effects significantly modify the standard picture of inflation in a wide class of models including new, natural, and hybrid inflation. We find that the quantum evolution of a single real…

High Energy Physics - Phenomenology · Physics 2010-01-06 D. Cormier , R. Holman