Related papers: Deviations from Hubble Flow in the Local Universe
Galaxies congregate in clusters and along filaments, and are missing from large regions referred to as voids. These structures are seen in maps derived from spectroscopic surveys that reveal networks of structure that are interconnected…
In this methodological paper we consider geodesic motion of particles in a spherically symmetric black hole space-times. We develop an approach based on splitting the velocity of a freely falling particle to the flow velocity, which depends…
What is the role of clusters of galaxies in probing the large-scale velocity field of the universe? We investigate the distribution of peculiar velocities of clusters of galaxies in the popular low-density ($\Omega=0.3$) flat…
Growth of the structure in the Universe manifest as accretion flows of galaxies onto groups and clusters. Thus, the present day properties of groups and their member galaxies are influenced by the characteristics of this continuous infall…
We use an all--sky, complete sample of nearby galaxies, extracted from the LEDA data base, to map the optical galaxy density field in the nearby universe. In order to determine this field, we correct the redshift--dependent distances by…
A kinematical analysis applied to a sample of galaxy clusters indicates that the differences between the velocity distribution of elliptical and spiral galaxies are associated with the shape of their orbit families. The orbital anisotropies…
The local galaxy distribution offers an interesting constraint to cosmological models of structure formation. The galaxies are distributed in a long, filamentary structure, presumably the result of large amplitude gravitational instability,…
Spiral galaxies can be affected by interactions in clusters, that also may distort the internal velocity field. If unrecognized from single-slit spectroscopy, this could lead to a wrong determination of the maximum rotation velocity as…
We show that by directly correlating the cluster kinetic Sunyaev Zeldovich (KSZ) flux, the cluster peculiar velocity power spectrum can be measured to $\sim 10%$ accuracy by future large sky coverage KSZ surveys. This method is almost free…
The concept of expanding space has come under fire recently as being inadequate and even misleading in describing the motion of test particles in the universe. Previous investigations have suffered from a number of shortcomings, which we…
(context) Different cosmological data are consistent with an accelerated expansion produced by an exotic matter-energy component, dubbed "dark-energy''. A cosmological constant is a possibility since it satisfies most of the observational…
It has been proposed recently to observe the change in cosmological redshift of distant galaxies or quasars with the next generation of large telescope and ultra-stable spectrographs (the so-called Sandage-Loeb test). Here we investigate…
In the first section of these lectures I outline the classical framework of the Hubble classification system. Because of space limitations I will focus on points of controversy concerning the physical interpretation of the Hubble sequence,…
We only see a small fraction of the matter in the universe, but the rest gives itself away by the impact of its gravity. Peculiar velocities have the potential to be a powerful tool to trace this matter however previous peculiar velocity…
The line-of-sight velocity dispersion profile of galaxy clusters exhibits a "kink" corresponding to the spatial extent of orbiting galaxies. Because the spatial extent of a cluster is correlated with the amplitude of the velocity dispersion…
We analyze the velocity field of peripheral members of the Local Group. The Hubble flow at distances from 400 to 1400~kpc, formed by 7 of 11 nearby galaxies, is characterized by an extremely small line-of-sight velocity dispersion of 15…
The dynamics of the Local Group and its environment provide a unique challenge to cosmological models. The velocity field within 5h-1 Mpc of the Local Group (LG) is extremely ``cold''. The deviation from a pure Hubble flow, characterized by…
Gravitational and hydrodynamical perturbations are analysed in a relativistic plasma containing a mixture of interacting fluids characterized by a non-negligible bulk viscosity coefficient. The energy-momentum transfer between the…
Our knowledge of the dynamics and masses of galaxies in the Local Group has long been limited by the fact that only line-of-sight velocities were observationally accessible. This introduces significant degeneracies in dynamical models,…
We show that the V_CMB velocities of the Fundamental Plane (FP) clusters studied in the Hubble Key Project appear to contain the same discrete "velocities" found previously by us and by Tifft to be present in normal galaxies. Although there…