English
Related papers

Related papers: The Curvaton Web

200 papers

As evidenced by a great number of works, it is common practice to assume that the Universe is flat. However, the majority of studies which make use of observational data to constrain the curvature density parameter are premised on the…

General Relativity and Quantum Cosmology · Physics 2019-07-18 Christine R. Farrugia , Joseph Sultana

We point out a possible generation mechanism of non-Gaussian bubbles in the sky due to bubble nucleation in the early universe. We consider a curvaton scenario for inflation and assume that the curvaton field phi, whose energy density is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Kazuyuki Sugimura , Daisuke Yamauchi , Misao Sasaki

In this paper, we show how the structure of the landscape potential of the primordial Universe may be probed through the properties of the primordial density perturbations responsible for the origin of the cosmic microwave background…

High Energy Physics - Theory · Physics 2019-09-25 Xingang Chen , Gonzalo A. Palma , Walter Riquelme , Bruno Scheihing Hitschfeld , Spyros Sypsas

Cosmic inflation provides a mechanism for generating the early density perturbations that seeded the large-scale structures we see today. Primordial non-Gaussianity is among the most promising of few observational tests of physics at this…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-10 Marilena LoVerde , Simone Ferraro , Kendrick M. Smith

We show that density fluctuations in standard inflationary scenarios may take the most general non-Gaussian distribution if the wave function of the Universe is not in the ground state. We adopt the Schr\"odinger picture to find a…

Astrophysics · Physics 2009-10-31 C. R. Contaldi , R. Bean , J. Magueijo

We propose a new mechanism to generate primordial curvature perturbations, based on the resonant production of particles during inflation. It is known that this phenomenon can trap the inflaton for a fraction of e-fold. This effect is…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-17 David Langlois , Lorenzo Sorbo

A new model realisation of the vector curvaton paradigm is presented and analysed. The model consists of a single massive Abelian vector field, with a Maxwell type kinetic term. By assuming that the kinetic function and the mass of the…

High Energy Physics - Phenomenology · Physics 2010-03-03 Konstantinos Dimopoulos , Mindaugas Karciauskas , Jacques M. Wagstaff

The cosmic web is one of the most complex systems in nature, consisting of galaxies and clusters of galaxies joined by filaments and walls, leaving large empty regions called cosmic voids. The most common method of describing the web is a…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-05 Jaan Einasto

The curvaton reheating mechanism in a Scale Invariant Two Measures Theory defined in terms of two independent non-Riemannian volume forms (alternative generally covariant integration measure densities) on the space-time manifold which are…

General Relativity and Quantum Cosmology · Physics 2015-11-30 Eduardo I. Guendelman , Ramon Herrera

In the presence of primordial isocurvature perturbations, for example in a separate dark radiation sector, the superhorizon evolution of curvature perturbations becomes nontrivial. If the dark sector is radiation-like and constitutes a…

High Energy Physics - Phenomenology · Physics 2025-10-28 Christopher Gerlach , Wolfram Ratzinger , Pedro Schwaller

We study non-linear primordial adiabatic and isocurvature perturbations and their non-Gaussianity. After giving a general formulation in the context of an extended delta N-formalism, we analyse in detail two illustrative examples. The first…

Astrophysics · Physics 2010-04-30 David Langlois , Filippo Vernizzi , David Wands

A three fluid system describing the decay of the curvaton is studied by numerical and analytical means. We place constraints on the allowed interaction strengths between the fluids and initial curvaton density by requiring that the curvaton…

Astrophysics · Physics 2010-01-06 Tuomas Multamaki , Jani Sainio , Iiro Vilja

Two-point correlation function of galaxy distribution shows that the structure in the present Universe is scale-free up to a certain scale (at least several tens Mpc), which suggests that a fractal structure may exist. If small primordial…

Astrophysics · Physics 2009-10-31 Takayuki Tatekawa , Kei-ichi Maeda

We show that the difference between the theoretically expected and measured by WMAP amplitude of the quadrupole fluctuations of CMB can be related to the impact of the anisotropic curvature of the homogeneous universe dominated by the dark…

Astrophysics · Physics 2008-11-26 M. Demiański , A. G. Doroshkevich

The large scale distribution of galaxies in the universe displays a complex pattern of clusters, super-clusters, filaments and voids with sizes limited only by the boundaries of the available samples. A quantitative statistical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Francesco Sylos Labini , Luciano Pietronero

Using both cosmic microwave background and large scale structure data, we put stringent bounds on the possible cold dark matter, baryon and neutrino isocurvature contributions to primordial fluctuations in the Universe. Neglecting the…

Astrophysics · Physics 2007-05-23 Juan Garcia-Bellido

In this work, one examines how the presence of a non-minimal coupling between the spacetime curvature and matter affects the evolution of cosmological perturbations around a homogeneous and isotropic Universe and hence the formation of…

General Relativity and Quantum Cosmology · Physics 2013-05-27 Orfeu Bertolami , Pedro Frazão , Jorge Páramos

The early Universe after inflation may have oscillations, kinations (nonoscillatory evolution of a field), topological defects, relativistic and non-relativistic particles at the same time. The Universe whose energy density is a sum of…

High Energy Physics - Phenomenology · Physics 2015-06-12 Seishi Enomoto , Kazunori Kohri , Tomohiro Matsuda

Inflating curvaton can create curvature perturbation when the curvaton density is slowly varying. Using the delta-N formalism, we discuss the evolution of the curvature perturbation during curvaton inflation and find analytic formulation of…

High Energy Physics - Phenomenology · Physics 2013-06-26 Seishi Enomoto , Kazunori Kohri , Tomohiro Matsuda

While galaxy cluster catalogs were compiled many decades ago, other structural elements of cosmic web are detected at definite level only in the newest works. For example, extragalactic filaments were described by velocity field and SDSS…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-19 A. V. Tugay
‹ Prev 1 4 5 6 7 8 10 Next ›