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Related papers: Violent Relaxation in Hierarchical Clustering

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Relaxation processes in collisionless dynamics lead to peculiar behavior in systems with long-range interactions such as self-gravitating systems, non-neutral plasmas and wave-particle systems. These systems, adequately described by the…

Statistical Mechanics · Physics 2011-12-30 Pierre de Buyl , Pierre Gaspard

Cosmological relaxation of the electroweak scale via Higgs-axion interplay, named as relaxion mechanism, provides a dynamical solution to the Higgs mass hierarchy. In the original proposal by Graham, Kaplan and Rajendran, the relaxion…

High Energy Physics - Phenomenology · Physics 2023-06-28 Aleksandr Chatrchyan , Géraldine Servant

The formation of galaxy clusters in hierarchically clustering universes is investigated by means of high resolution N-body simulations. The simulations are performed using a newly developed multi-mass scheme which combines a PM code with a…

Astrophysics · Physics 2007-05-23 A. Huss , B. Jain , M. Steinmetz

We apply the well known semi analytical model of formation of DM halos to discuss the process of formation and evolution of the relaxed objects dominated by the DM component (such as the first and dSph galaxies and clusters of galaxies). On…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Marek Demiański , Andrey Doroshkevich

N-body simulations of the hierarchical formation of cosmic structures suffer from the problem that the first objects to form always contain just a few particles. Although relaxation is not an issue for virialised objects containing millions…

Astrophysics · Physics 2009-11-07 Juerg Diemand , Ben Moore , Joachim Stadel , Stelios Kazantzidis

Clusters of galaxies are studied from a theoretical point of view, comparing with observational results whenever possible. The problem is approached both analytically as well as by means of high-resoultion numerical simulations. The dark…

Astrophysics · Physics 2007-05-23 Y. Ascasibar

A new model for the postcollapse equilibrium structure of virialized objects which condense out of the cosmological background universe is described and compared with observations and simulations of cosmological halos from dwarf galaxies to…

Astrophysics · Physics 2009-09-25 Paul R. Shapiro , Ilian T. Iliev

In hierarchical cosmologies the evolution of galaxy clustering depends both on cosmological quantities such as Omega and Lambda, which determine how dark matter halos form and evolve, and on the physical processes - cooling, star formation…

We provide a physical interpretation and explanation of the morphology-density relation for galaxies, drawing on stellar masses, star formation rates, axis ratios and group halo masses from the Sloan Digital Sky Survey. We first re-cast the…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-28 Arjen van der Wel , Eric F. Bell , Bradford P. Holden , Ramin A. Skibba , Hans-Walter-Rix

We introduce a new simple hierarchically constrained model of slow relaxation. The configurational energy has a simple form as there is no coupling among the spins defining the system; the associated stationary distribution is an…

Condensed Matter · Physics 2009-10-30 M. A. Muñoz , A. Gabrielli , H. Inaoka , L. Pietronero

The traditional Chandrasekhar picture of the slow relaxation of stellar systems assumes that stars' orbits are only modified by occasional, uncorrelated, two-body flyby encounters with other stars. However, the long-range nature of gravity…

Astrophysics of Galaxies · Physics 2020-12-01 Chris Hamilton , Tobias Heinemann

The nonexponential relaxation ocurring in complex dynamics manifested in a wide variety of systems is analyzed through a simple model of diffusion in phase space. It is found that the inability of the system to find its equilibrium state in…

Statistical Mechanics · Physics 2009-11-10 A. Perez-Madrid

The origin of equilibrium gravitational configurations is sought in terms of the stability of their trajectories, as described by the curvature of their Lagrangian configuration manifold of particle positions --- a context in which subtle…

Astrophysics of Galaxies · Physics 2015-06-17 Amr El-Zant

The most massive halos of matter in the Universe grow via accretion and merger events throughout cosmic times. These violent processes generate shocks at many scales and induce large-scale bulk and turbulent motions. These processes inject…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-16 Simon Dupourqué , Etienne Pointecouteau , Nicolas Clerc , Dominique Eckert

This paper explores the phenomenon of energy relaxation for stars in a galaxy embedded in a high density environment that is subjected continually to perturbations reflecting the presence of other nearby galaxies and/or incoherent internal…

Astrophysics · Physics 2015-06-24 Henry E. Kandrup

The formation, inner properties, and spatial distribution of galaxy groups and clusters are closely related to the background cosmological model. We use numerical simulations of variants of the CDM model with different cosmological…

Astrophysics · Physics 2011-05-23 Alexander Knebe , Volker Mueller

This paper explores how orbits in a galactic potential can be impacted by large amplitude time-dependences of the form that one might associate with galaxy or halo formation or strong encounters between pairs of galaxies. A period of…

Astrophysics · Physics 2009-11-07 Henry E. Kandrup , Ileana M. Vass , Ioannis V. Sideris

This paper aims at quantifying discreetness effects, born of finite particle number, on the dynamics of dark matter haloes forming in the context of cosmological simulations. By generalising the standard calculation of two body relaxation…

Astrophysics · Physics 2009-11-11 Amr El-Zant

In general, classical fully-connected systems are known to undergo violent relaxation. This phenomenon refers to the relaxation of observables to stationary, non-thermal, values on a finite timescale, despite their long-time dynamics being…

Quantum Physics · Physics 2025-06-17 Guido Giachetti , Nicolò Defenu

In a series of recent papers, a new formalism has been developed that explains the inner structure of dark matter halos as collisionless, dissipationless systems assembled through mergers and accretion at the typical cosmological rate.…