Related papers: Local Gravity versus Local Velocity: Solutions for…
We derive peculiar velocities for the 6dF Galaxy Survey (6dFGS) and describe the velocity field of the nearby ($z<0.055$) southern hemisphere. The survey comprises 8885 galaxies for which we have previously reported Fundamental Plane data.…
Deviations from general relativity in order to explain cosmic acceleration generically have both time and scale dependent signatures in cosmological data. We extend our previous work by investigating model independent gravitational…
We present preliminary results from the Shellflow program, an all-sky Tully-Fisher (TF) survey of 297 Sb-Sc with redshifts between 4000 and 7500 km/s. The program was designed to ensure uniformity of the data between observing runs and…
We use observations and simulation to study the relationship between star-forming galaxies and the intergalactic medium at z~3. The observed galaxy sample is based on spectroscopic redshift data from a combination of the VLT LBG Redshift…
In this paper we investigate how observational effects could possibly bias cosmological inferences from peculiar velocity measurements. Specifically, we look at how bulk flow measurements are compared with theoretical predictions. Usually…
We have used integral field spectroscopy of a sample of six nearby (z~0.01-0.04) high star-formation rate (SFR~10-40 solar masses per year) galaxies to investigate the relationship between local velocity dispersion and star formation rate…
Reviews observational situation in the measurement of peculiar velocities in the local universe. Emphasis is placed on such topics as: Do spirals and ellipticals yield the same peculiar velocity field? What is the cluster velocity…
We review observational tests for the homogeneity of the Universe on large scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray Background, the Lyman-$\alpha$ forest and the Cosmic Microwave Background are used to set…
f(R) gravity is thought to be an alternative to dark energy which can explain the acceleration of the universe. It has been tested by different observations including type Ia supernovae (SNIa), the cosmic microwave background (CMB), the…
We measure the distribution function of rotational velocities phi(V_c) of late-type galaxies from the HIPASS galaxy catalogue. Previous measurements of the late-type velocity function are indirect, derived by converting the galaxy…
Strong gravitational lensing provides an independent and powerful probe of cosmic expansion by directly linking observables to cosmological distances. Upcoming surveys such as LSST will discover large number of galaxy-galaxy strong lensing…
We present a version of the Fourier Bessel method first introduced by Fisher et al (1994) and Zaroubi et al (1994) with two extensions: (a) we amend the formalism to allow a generic galaxy weight which can be constant rather than the more…
The pair-weighted relative velocity dispersion of galaxies provides a measure of the thermal energy of fluctuations of the observed galaxy distribution, but the measure is difficult to interpret and is very sensitive to the existence of…
We test the hypothesis that the velocity field derived from Tully-Fisher measurements of spiral galaxies, and that derived independently from Dn-sigma measurements of ellipticals and S0s, are noisy versions of the same underlying velocity…
Peculiar velocities thoughout the region of the local supercluster are reconstructed by two different orbit-retracing methods. The requirement of the optimal correlation between the radial components of reconstructed velocities and the…
Our statistical studies comprise the mean relative velocity and velocity correlation for pairs of galaxies as a function of separation, and a bulk flow analysis determined on spheres of $10 h^{-1}$ $Mpc$ radius. In order to test the…
The peculiar velocity of a mass tracer is on average aligned with the dipole modulation of the surrounding mass density field. We present a first measurement of the correlation between radial peculiar velocities of objects in the…
I derive a nonlinear local relation between the redshift-space density field and the real-space velocity field. The relation accounts for radial character of redshift distortions, and it is not restricted to the limit of the distant…
The galaxy density field as extracted from the IRAS 1.2 Jy redshift survey is compared to the mass density field as reconstructed by the POTENT method from the Mark III catalog of peculiar velocities. The reconstruction is done with…
Observed galaxy luminosities (derived from redshifts) hold information on the large-scale peculiar velocity field in the form of spatially correlated scatter, which allows for bounds on bulk flows and the growth rate of matter density…