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Related papers: Large-Scale Velocity Dispersion and the Cosmic Web

200 papers

We study the dynamics of gravitationally collapsing massive shells in AdS spacetime, and show in detail how one can determine extremal surfaces traversing them. The results are used to solve the time evolution of the holographic…

High Energy Physics - Theory · Physics 2015-04-01 Ville Keranen , Hiromichi Nishimura , Stefan Stricker , Olli Taanila , Aleksi Vuorinen

We investigate the evolution of non-adiabatic collapse of a shear-free spherically symmetric stellar configuration with anisotropic stresses accompanied with radial heat flux. The collapse begins from a curvature singularity with infinite…

General Relativity and Quantum Cosmology · Physics 2013-04-30 R. Sharma , R. Tikekar

A new approach for the classification of the cosmic web is presented. In extension of the previous work of Hahn et al. (2007) and Forero-Romero et al. (2009) the new algorithm is based on the analysis of the velocity shear tensor rather…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-17 Yehuda Hoffman , Ofer Metuki , Gustavo Yepes , Stefan Gottlöber , Jaime E. Forero-Romero , Noam I. Libeskind , Alexander Knebe

In the interstellar medium of galaxies and the intracluster gas of galaxy clusters, the charged particles making up cosmic rays are moving almost exclusively along (but not across) magnetic field lines. The resulting anisotropic transport…

Astrophysics of Galaxies · Physics 2016-08-31 Ruediger Pakmor , Christoph Pfrommer , Christine M. Simpson , Rahul Kannan , Volker Springel

We consider a cosmological model in which the two major fluid components of the Universe, dark energy and dark matter, flow with distinct four-velocities. This cosmological configuration is equivalent to a single anisotropic fluid,…

General Relativity and Quantum Cosmology · Physics 2013-07-24 Tiberiu Harko , Francisco S. N. Lobo

We measure the three components of velocity dispersion, $\sigma_{R},\sigma_{\theta},\sigma_{\phi}$, for stars within 6 < R < 30 kpc of the Milky Way using a new radial velocity sample from the MMT telescope. We combine our measurements with…

Astrophysics of Galaxies · Physics 2015-11-11 Charles King , Warren R. Brown , Margaret J. Geller , Scott J. Kenyon

We investigate a simple inhomogeneous anisotropic cosmology (plane symmetric $G_2$ model) filled with a tilted perfect fluid undergoing velocity diffusion on a scalar field. Considered are two types of fluid: dust and radiation. We solve…

General Relativity and Quantum Cosmology · Physics 2014-11-13 Dmitry Shogin , Sigbjorn Hervik

Velocity fields in the cosmic web are fundamental to structure formation but remain difficult to observe directly beyond the linear regime. Here we present observational evidence that galaxy filaments connecting pairs of galaxy clusters…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Ji Yao , Huanyuan Shan , Pengjie Zhang , Xiaohu Yang , Jiale Zhou , Jiaxin Han , Peng Wang

The velocity dispersion-size relation ($\sigma_{\rm v}\sim R^{\beta}$) is a crucial indicator of the dynamic properties of interstellar gas, where the slope is considered as $\beta \sim 0.5$. Recent observations reveal a steep velocity…

Astrophysics of Galaxies · Physics 2025-05-14 Yi-Heng Xie , Guang-Xing Li

Basing our discussion on the Lagrangian description of hydrodynamics, we studied the evolution of density fluctuation for nonlinear cosmological dynamics. Adhesion approximation (AA) is known as a phenomenological model that describes the…

Astrophysics · Physics 2009-11-10 Takayuki Tatekawa

Understanding the structure of the matter distribution in the Universe due to the action of the gravitational instability -- the cosmic web -- is complicated by lack of direct analytic access to the nonlinear domain of structure formation.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Sergei Shandarin , Salman Habib , Katrin Heitmann

Galactic nuclei, the densest stellar environments in the Universe, exhibit a complex geometrical structure. The stars orbiting the central supermassive black hole follow a mass segregated distribution both in the radial distance from the…

Astrophysics of Galaxies · Physics 2023-10-24 Hanxi Wang , Bence Kocsis

Under nonuniform convection, the distribution of diffusive particles can exhibit dipole and quadrupole anisotropy induced by the fluid inertial and shear force, respectively. These convection-related anisotropies, unlike the Compton-Getting…

High Energy Astrophysical Phenomena · Physics 2022-10-26 Yiran Zhang , Siming Liu , Dejin Wu

The collisionless quasi-equilibrium state realized after the cold collapse of self-gravitating systems has two remarkable characters. One of them is the linear temperature-mass (TM) relation, which yields a characteristic non-Gaussian…

Astrophysics · Physics 2009-11-13 Y. Sota , O. Iguchi , M. Morikawa , A. Nakamichi

Molecular cloud observations show that clouds have non-thermal velocity dispersions that scale with the cloud size as $\sigma\propto R^{1/2}$ at constant surface density, and for varying surface density scale with both the cloud`s size and…

Astrophysics of Galaxies · Physics 2016-06-15 Juan C. Ibáñez-Mejía , Mordecai-Mark Mac Low , Ralf S. Klessen , Christian Baczynski

The peculiar motion of the Earth causes a dipole anisotropy modulation in the distant galaxy distribution due to the aberration effect. However, the amplitude and angular direction of the effect is not necessarily the same as those of the…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-12 Yousuke Itoh , Kazuhiro Yahata , Masahiro Takada

In this paper, we have considered a toy model of an anisotropic universe and studied the propagation of gravitational waves in such a universe. The consideration of this toy model simplifies the analysis and helps us to illustrate the…

General Relativity and Quantum Cosmology · Physics 2019-08-20 Sucheta Datta , Sarbari Guha

There is a well-established relation between the spatial asymmetry in the initial stage of a heavy-ion collision and the final momentum anisotropy, which allows for a separation of effects from initial conditions vs. later evolution and has…

Nuclear Theory · Physics 2020-06-04 Rodrigo Franco , Matthew Luzum

Nonequilibrium molecular dynamics simulations are used to study the deformation behavior of disperse polymer melts by tracking test chains of length N = Mw, the weight average molecular weight, in melts of varying dispersity. At high strain…

Soft Condensed Matter · Physics 2025-07-29 Taofeek Tejuosho , Janani Sampath

We investigate spherically symmetric gravitational collapse of thick matter shell without radiation in the Einstein gravity with cosmological constant. The orbit of the infalling thick matter is determined by imposing an equation of state…

General Relativity and Quantum Cosmology · Physics 2023-01-10 Shuichi Yokoyama