English
Related papers

Related papers: Anisotropy in a Nonsingular Bounce

200 papers

We study the dynamics of states perturbatively expanded about a harmonic system of loop quantum cosmology, exhibiting a bounce. In particular, the evolution equations for the first and second order moments of the system are analyzed. These…

General Relativity and Quantum Cosmology · Physics 2011-01-20 Martin Bojowald , David Mulryne , William Nelson , Reza Tavakol

We construct general anisotropic cosmological scenarios governed by an $f(R)$ gravitational sector. Focusing then on Kantowski-Sachs geometries in the case of $R^n$-gravity, and modelling the matter content as a perfect fluid, we perform a…

General Relativity and Quantum Cosmology · Physics 2011-08-19 Genly Leon , Emmanuel N. Saridakis

The formation and collapse of a protostar involves the simultaneous infall and outflow of material in the presence of magnetic fields, self-gravity, and rotation. We use self-similar techniques to self-consistently model the anisotropic…

Astrophysics · Physics 2016-01-13 Mahmoud Aburihan , Jason D. Fiege , Richard N. Henriksen , Thibaut Lery

Recently a Born-Infeld action for dark energy and dark matter that uses additional affine connections was proposed. At background level, it was shown that the new proposal can mimic the standard cosmological evolution. In Bianchi…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Davi C. Rodrigues

It is believed that soon after the Planck era, spacetime should have a semi-classical nature. Therefore, it is unavoidable to modify the theory of General Relativity or look for alternative theories of gravitation. An interesting…

General Relativity and Quantum Cosmology · Physics 2013-08-01 Daniel Müller , Márcio E. S. Alves , José C. N. de Araujo

In hyperbolic reductions of the Einstein equations the evolution of gauge conditions or constraint quantities is controlled by subsidiary systems. We point out a class of non-linearities in these systems which may have the potential of…

General Relativity and Quantum Cosmology · Physics 2010-11-05 Helmut Friedrich

We discuss two methods by which high porosity silica aerogels can be engineered to exhibit global anisotropy. First, anisotropy can be introduced with axial strain. In addition, intrinsic anisotropy can result during growth and drying…

Other Condensed Matter · Physics 2009-11-13 J. Pollanen , K. Shirer , S. Blinstein , J. P. Davis , H. Choi , T. M. Lippman , L. B. Lurio , W. P. Halperin

Using in situ grazing-incidence x-ray scattering, we have measured the diffuse scattering from islands that form during layer-by-layer growth of GaN by metal-organic vapor phase epitaxy on the (1010) m-plane surface. The diffuse scattering…

In weakly collisional stellar systems such as some globular clusters, partial energy equipartition and mass segregation are expected to develop as a result of the cumulative effect of stellar encounters even in systems initially…

Astrophysics of Galaxies · Physics 2019-12-04 Stefano Torniamenti , Giuseppe Bertin , Paolo Bianchini

We show that a nonsingular bounce, free of ghosts and gradient instabilities, can be realized in the framework of Horndeski or generalized Galileon cosmology. In particular, we first review that the theoretical no-go theorem, which states…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Shreya Banerjee , Yi-Fu Cai , Emmanuel N. Saridakis

Lagrangian statistics of passive tracers in rotating turbulence is investigated by Particle Tracking Velocimetry. A confined and steadily-forced turbulent flow is subjected to five different rotation rates. The PDFs of the velocity…

Fluid Dynamics · Physics 2013-07-24 Lorenzo Del Castello , Herman J. H. Clercx

We investigate the time evolution of the six-component electron pressure tensor in a hybrid code studying consequences for the two-dimensional reconnection process in an initially perturbed Harris sheet. We put forward that two tensor…

Plasma Physics · Physics 2021-07-23 A. Sladkov , R. Smets , N. Aunai , A. Korzhimanov

Non-attractor inflation is known as the only single field inflationary scenario that can violate non-Gaussianity consistency relation with the Bunch-Davies vacuum state and generate large local non-Gaussianity. However, it is also known…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-08 Yi-Fu Cai , Xingang Chen , Mohammad Hossein Namjoo , Misao Sasaki , Dong-Gang Wang , Ziwei Wang

We consider evolutions of linear fluctuations as the background Friedmann world model goes from contracting to expanding phases through smooth and non-singular bouncing phases. As long as the gravity dominates over the pressure gradient in…

Astrophysics · Physics 2009-11-07 J. Hwang , H. Noh

Space-time picture of the anisotropic flow evolution in Au+Au collisions at BNL RHIC is studied for strange hadrons within the microscopic quark-gluon string model. The directed flow of both mesons and hyperons demonstrates wiggle structure…

High Energy Physics - Phenomenology · Physics 2009-11-11 E. Zabrodin , L. Bravina , G. Burau , J. Bleibel , C. Fuchs , Amand Faessler

We study holographic isotropisation of homogeneous, strongly coupled, non-Abelian plasmas in Gauss-Bonnet gravity with a negative cosmological constant. We focus on small values of the Gauss-Bonnet coupling parameter $\lambda_{GB}$ and…

High Energy Physics - Theory · Physics 2017-03-08 Tomas Andrade , Jorge Casalderrey-Solana , Andrej Ficnar

We present a rigorous formulation of the Quantum Big Bounce for the closed isotropic Universe, filled with a self-interacting scalar field, that emerges from the interaction with an ekpyrotic potential. Working in a covariant approach to…

General Relativity and Quantum Cosmology · Physics 2026-03-09 S. Lo Franco , G. Montani

We formulate a generalisation of the blast-wave model which is suitable for the description of higher order azimuthal anisotropies of the hadron production. The model includes anisotropy in the density profile as well as an anisotropy in…

Nuclear Theory · Physics 2017-08-09 Jakub Cimerman , Boris Tomasik , Mate Csanad , Sandor Lokos

We study the phase transition dynamics of a fluid system in which the particles diffuse anisotropically in space. The motivation to study such a situation is provided by systems of interacting magnetic colloidal particles subject to the…

Soft Condensed Matter · Physics 2018-10-04 Hidde Derk Vuijk , Joseph Michael Brader , Abhinav Sharma

Massive scalar particle production, due to the anisotropic evolution of a five-dimensional spacetime, is considered in the context of a quadratic Lagrangian theory of gravity. Those particles, corresponding to field modes with non-vanishing…

General Relativity and Quantum Cosmology · Physics 2014-11-17 K. Kleidis , D. B. Papadopoulos