相关论文: Bulk Motions in Large-Scale Void Models
We determine the velocity correlation function, pairwise peculiar velocity difference, and root-mean-square pairwise peculiar velocity dispersion of rich clusters of galaxies, as a function of pair separation, for three cosmological models:…
This work investigates the impact of cosmic flows and density perturbations on Hubble constant $H_0$ measurements using nonlinear phase-space reconstructions of the Local Universe (LU). In particular, we rely on 25 constrained N-body…
The peculiar motions of galaxies can be used to infer the distribution of matter in the Universe. It has recently been shown that measurements of the peculiar velocity field indicates an anomalously high bulk flow of galaxies in our local…
Lauer \& Postman (LP) observe that all Abell clusters with redshifts less than 15,000\kms\ appear to be participating in a bulk flow of 689 km s$^{-1}$ with respect to the Cosmic Microwave Background. We find this result difficult to…
In preceding papers of this series, TF relations for galaxies in 24 clusters with radial velocities between 1000 and 9200 km/s (SCI sample) were obtained, a Tully-Fisher (TF) template relation was constructed and mean offsets of each…
We address recently reported anomalously large bulk flows on scales of 100 Mpc/h and beyond. These coherent motions of galaxies challenge the standard LCDM concordance model as well as a large class of competitive models of dark energy and…
A significant tension has become manifest between the current expansion rate of our Universe measured from the cosmic microwave background by the Planck satellite and from local distance probes, which has prompted for interpretations of…
Cosmological parameters are constrained by a wide variety of observations. We examine the concordance diagram for modern measurements of the Hubble constant, the shape parameter from large scale structure, the cluster baryon fraction, and…
We calculate the off--center observational relations in a spherically symmetric dust universe that is inhomogeneous at small redshifts. In contrast to the usual model, in which the CMBR dipole is interpreted as a Doppler effect due to…
The velocity dispersion of galaxies on small scales ($r\sim1h^{-1}$ Mpc), $\sigma_{12}(r)$, can be estimated from the anisotropy of the galaxy-galaxy correlation function in redshift space. We apply this technique to ``mock-catalogs''…
The large scale distribution of galaxies in the universe displays a complex pattern of clusters, super-clusters, filaments and voids with sizes limited only by the boundaries of the available samples. A quantitative statistical…
Repeated studies of the CMB based on WMAP data have revealed an apparent asymmetry in the distribution of temperature fluctuations over the celestial sphere. The studies indicate that the amplitudes of temperature fluctuations are higher in…
Using N-body simulations of flat, dark energy dominated cosmologies, we show that galaxies around simulated binary systems resembling the Local Group (LG) have low peculiar velocities, in good agreement with observational data. We have…
In this study, we use the merger process of clusters/voids in the role of variable dark energy fluid to alleviate the Hubble tension, which can lead to a balance in the cosmological expansion rate. To reach this target, we will introduce a…
As tracers of the underlying mass distributions, the peculiar velocities of galaxies are valuable probes of the Universe, allowing us to measure the Hubble constant or to map the large-scale structure and its dynamics. The catalogs of…
By performing a global magneto-hydrodynamical simulation for the Milky Way with an axisymmetric gravitational potential, we propose that spatially dependent amplification of magnetic fields possibly explains the observed noncircular motion…
We examine high-resolution gravitational N-body simulations of the $\Omega=1$ cold dark matter (CDM) model in order to determine whether there is any normalization of the initial density fluctuation spectrum that yields acceptable results…
Bulk peculiar flows are commonplace in the universe, with many surveys reporting their presence on scales spanning between few hundred and several hundred Mpc. However, the sizes and the speeds of some of these bulk flows are well in excess…
Voids are dominant features of the cosmic web. We revisit the cosmological information content of voids and connect void properties with the parameters of the background universe. We combine analytical results with a suite of large n-body…
We report first results from the ``Streaming Motions of Abell Clusters'' (SMAC) project, an all-sky Fundamental Plane survey of 699 early-type galaxies in 56 clusters between ~3000 km/s and ~14000 km/s. For this sample, with a median…