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Related papers: Nonlinear evolution of density and flow perturbati…

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We define fully non-perturbative generalizations of the uniform density and comoving curvature perturbations, which are known, in the linear theory, to be conserved on sufficiently large scales for adiabatic perturbations. Our non-linear…

Astrophysics · Physics 2009-11-10 David Langlois , Filippo Vernizzi

Recent studies have shown that fluctuations of various types play important roles in the evolution of the fireball created in relativistic heavy ion collisions and bear many phenomenological consequences for experimental observables. The…

High Energy Physics - Theory · Physics 2015-01-07 Shuzhe Shi , Jinfeng Liao , Pengfei Zhuang

Initial fluctuations in hydrodynamic fields such as energy density or flow velocity give access to understanding initial state and equilibration physics as well as thermodynamic and transport properties. We provide evidence that the fluid…

High Energy Physics - Phenomenology · Physics 2015-06-22 Stefan Floerchinger , Urs Achim Wiedemann , Andrea Beraudo , Luca Del Zanna , Gabriele Inghirami , Valentina Rolando

Oscillations in the primordial bispectrum are sourced by a range of inflationary phenomena, including features in the inflaton potential and interactions with massive fields through the Cosmological Collider scenario. These signatures offer…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-20 Samuel Goldstein , Oliver H. E. Philcox , Emanuele Fondi , William R. Coulton

Studies of the growth of cosmic perturbations are typically focused on galactic scales and above. In this paper we investigate the evolution of perturbations in baryons, photons, and dark matter for masses below 10^6 M_\odot (or wavenumbers…

Astrophysics · Physics 2009-11-07 Shwetabh Singh , Chung-Pei Ma

We generalize the spherical collapse model for the formation of bound objects to apply in a Universe with arbitrary positive cosmological constant. We calculate the critical condition for collapse of an overdense region and give exact…

Astrophysics · Physics 2007-05-23 Ewa L. Lokas , Yehuda Hoffman

Nonlinear evolution equations of the fourth order and its partial cases are derived for describing nonlinear pressure waves in a mixture liquid and gas bubbles. Influence of viscosity and heat transfer is taken into account. Exact solutions…

Pattern Formation and Solitons · Physics 2011-12-23 Nikolay A. Kudryashov , Dmitry I. Sinelshchikov

The dynamics of models described by a one-dimensional discrete nonlinear Schr\"odinger equation is studied. The nonlinearity in these models appears due to the coupling of the electronic motion to optical oscillators which are treated in…

Condensed Matter · Physics 2009-10-28 P. K. Datta , K. Kundu

Longitudinal hydrodynamic expansion of the fluid created in relativistic heavy-collisions is considered taking into account shear viscosity. Both a on-vanishing viscosity and a soft equation of state make particle distributions in rapidity…

Nuclear Theory · Physics 2009-04-13 Piotr Bozek

Nonlinear waves are studied in a mixture of liquid and gas bubbles. Influence of viscosity and heat transfer is taken into consideration on propagation of the pressure waves. Nonlinear evolution equations of the second and the third order…

Pattern Formation and Solitons · Physics 2011-12-23 Nikolay A. Kudryashov , Dmitry I. Sinelshchikov

We determine the behavior of an out-of-equilibrium superfluid, composed of a $U(1)$ Goldstone mode coupled to hydrodynamic modes in a M\" uller-Israel-Stewart theory, in expanding backgrounds relevant to heavy ion collision experiments and…

High Energy Physics - Phenomenology · Physics 2026-05-21 Guri K. Buza , Toshali Mitra , Alexander Soloviev

The non-perturbative curvature inhomogeneities induced by relativistic viscous fluids are not conserved in the large-scale limit. However when the bulk viscosity is a function of the total energy density of the plasma (or of the trace of…

High Energy Physics - Theory · Physics 2015-08-06 Massimo Giovannini

The subject of moving curves (and surfaces) in three dimensional space (3-D) is a fascinating topic not only because it represents typical nonlinear dynamical systems in classical mechanics, but also finds important applications in a…

Pattern Formation and Solitons · Physics 2015-06-26 S. Murugesh , M. Lakshmanan

Fluctuation and dissipation dynamics is examined at all temperature ranges for the general case of a background time evolving scalar field coupled to heavy intermediate quantum fields which in turn are coupled to light quantum fields. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Arjun Berera , Ian G. Moss , Rudnei O. Ramos

A model of the thin shell expanding into a uniform ambient medium is developed. Density perturbations are described using equations with linear and quadratic terms, and the linear and the nonlinear solutions are compared. We follow the time…

Astrophysics · Physics 2007-05-23 R. Wunsch , J. Palous

Photons and dileptons are emitted throughout the evolution of the deconfined nuclear medium produced in heavy ion collisions. As such they can provide valuable information about the different phases of the medium, and complement hadronic…

Nuclear Theory · Physics 2018-03-14 Jean-François Paquet

We propose a theoretical and computational approach to investigate temporal behavior of a nonlinear polarization in perturbative regime induced by an intense and ultrashort pulsed electric field. First-principles time-dependent density…

Optics · Physics 2019-03-27 Mitsuharu Uemoto , Yuki Kuwabara , Shunsuke A. Sato , Kazuhiro Yabana

Using anisotropic hydrodynamics, we examine the existence of early-time attractors of non-conformal systems undergoing Bjorken expansion. In the case of a constant mass, we find that the evolution of the scaled longitudinal pressure is…

Nuclear Theory · Physics 2023-05-01 Mubarak Alqahtani

The analysis of nonlinear wave equations has experienced a dramatic growth in the last ten years or so. The key factor in this has been the transition from linear analysis, first to the study of bilinear and multilinear wave interactions,…

Analysis of PDEs · Mathematics 2007-05-23 Daniel Tataru

We study the evolution of linear density perturbations in a large spherical void universe which accounts for the acceleration of the cosmic volume expansion without introducing dark energy. The density contrast of this void is not large…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-07 Ryusuke Nishikawa , Chul-Moon Yoo , Ken-ichi Nakao