English
Related papers

Related papers: Clumps into Voids

200 papers

In a four dimensional manifold formalism we study the evolutionary behavior as well as the ultimate fate of the universe, in the course of which the contribution of dark energy in these phases are investigated. At one stage we get a…

General Relativity and Quantum Cosmology · Physics 2018-11-13 Koijam Manihar Singh , Gauranga C. Samanta

We study the structure of shocks in clumpy media, using a multifluid formalism. As expected, shocks broaden as they weaken: for sufficiently weak shocks, no viscous subshock appears in the structure. This has significant implications for…

Astrophysics · Physics 2009-11-07 R. J. R. Williams , J. E. Dyson

Spatiotemporal patterns in nature, such as ripples or dunes, formed by a fluid streaming over a sandy surface show complex behavior despite their simple forms. Below the surface, the granular structure of the sand particles is subject to…

Soft Condensed Matter · Physics 2015-05-30 Christopher Groh , Ingo Rehberg , Christof A. Kruelle

Further to results in [9], pointing out the role of initial density and velocity distributions towards determining the final outcome of spherical dust collapse, the causal structure of singularity is examined here in terms of evolution of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sanjay Jhingan , P. S. Joshi , T. P. Singh

We trace the evolution of a spherically symmetric density perturbation in the MOdified Newtonian Dynamics (MOND) model. The background cosmological model is a $\Lambda$-dominated, low-$\Omega_b$ Friedmann model with no Cold Dark Matter. We…

Astrophysics · Physics 2007-05-23 Slawomir Stachniewicz , Marek Kutschera

Within the coexistence region between liquid and vapor the equilibrium pressure of a simulated fluid exhibits characteristic jumps and plateaus when plotted as a function of density at constant temperature. These features exclusively…

Statistical Mechanics · Physics 2015-09-09 S. Prestipino , C. Caccamo , D. Costa , G. Malescio , G. Munaò

To clarify observational consequence of bubble nucleations in inflationary era, we analyse dynamics of a spherical domain wall in an expanding universe. We consider a spherical shell of the domain wall with tension $\sigma$ collapsing in a…

General Relativity and Quantum Cosmology · Physics 2015-08-06 Norihiro Tanahashi , Chul-Moon Yoo

Structure formation creates high temperature and density regions in the Universe that allow the conversion of matter into more stable states, with a corresponding emission of relativistic matter and radiation. An example of such a mechanism…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-11 D. Boriero , P. C. de Holanda , M. Motta

Cosmological perturbation equations derived from low-energy effective actions are shown to be invariant under a duality transformation reminiscent of electric-magnetic, strong-weak coupling, S-duality. A manifestly duality-invariant…

High Energy Physics - Theory · Physics 2009-10-31 R. Brustein , M. Gasperini , G. Veneziano

Large-scale structure of Universe includes galaxy clusters connected by filaments. Voids occupy the rest of cosmic volume. The search of any dependencities in filament structure can give answer to more general questions about origin of…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-09 V. V. Voitsekhovskiy , A. V. Tugay

Particles in pressure-driven channel flow are often inhomogeneously distributed. Two modes of low-Reynolds number instability, absent in Poiseuille flow of clean fluid, are created by inhomogeneous particle loading, and their mechanism is…

Fluid Dynamics · Physics 2024-11-27 Anup Kumar , Rama Govindarajan

If a theory has more than one classically stable vacuum, quantum tunneling and thermal jumps make the transition between the vacua possible. The transition happens through a first order phase transition started by nucleation of a bubble of…

High Energy Physics - Theory · Physics 2015-05-26 Ali Masoumi

We consider a dusty clump in the two cases of spherical and cylindrical symmetry to investigate the effect of temperature and density gradients on the observed flux density. Conversely, we evaluate how the presence of such gradients affects…

Astrophysics of Galaxies · Physics 2019-10-23 Riccardo Cesaroni

This article reviews an approach for constructing a simple relativistic fractal cosmology whose main aim is to model the observed inhomogeneities of the distribution of galaxies by means of the Lemaitre-Tolman solution of Einstein's field…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-27 Marcelo B. Ribeiro

Using the exact Lemaitre-Bondi-Tolman solution with a non-vanishing cosmological constant $\Lambda$, we investigate how the presence of a local spherically-symmetric inhomogeneity can affect apparent cosmological observables, such as the…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-01 Antonio Enea Romano , Misao Sasaki , Alexei A. Starobinsky

Cosmic voids are underdense regions filling up most of the volume in the Universe. They are expected to emerge in regions comprising negative initial density fluctuations, and subsequently expand as the matter around them collapses and…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-07 David Vallés-Pérez , Vicent Quilis , Susana Planelles

We explore the effects coming from the nested structures on propagation of radial light rays going through them in the simple self-similar configuration containing pairs of voids and overdense regions. Each pair can be described with the…

General Relativity and Quantum Cosmology · Physics 2017-05-25 Jarosław Kopiński

We investigate a general relativistic mechanism in which spikes generate matter overdensities in the early universe. When the cosmological fluid is tilted, the tilt provides another mechanism in generating matter inhomogeneities. We…

General Relativity and Quantum Cosmology · Physics 2015-07-13 Woei Chet Lim , Alan Coley

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

We investigate the occurrence and nature of a naked singularity in the gravitational collapse of an inhomogeneous dust cloud described by a self-similar higher dimensional Tolman-Bondi space-time. Bound, marginally bound and unbound…

General Relativity and Quantum Cosmology · Physics 2009-11-07 S. G. Ghosh , A. Banerjee