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We perform a statistical study of the global motion of cosmic voids using both a numerical simulation and observational data. We analyse their relation to large-scale mass flows and the physical effects that drive those motions. We analyse…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-07 Laura Ceccarelli , Andrés N. Ruiz , Marcelo Lares , Dante J. Paz , Victoria E. Maldonado , Heliana E. Luparello , Diego Garcia Lambas

We present a method for deriving a smoothed estimate of the peculiar velocity field of a set of galaxies with measured circular velocities $\eta\equiv {\rm log} \Delta v$ and apparent magnitudes $m$. The method is based on minimizing the…

Astrophysics · Physics 2015-06-24 Adi Nusser , Marc Davis

The estimation and analysis of large-scale bulk flow moments of peculiar velocity surveys is complicated by non-spherical survey geometry, the non-uniform sampling of the matter velocity field by the survey objects and the typically large…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-28 Shankar Agarwal , Hume A. Feldman , Richard Watkins

We review the use of peculiar velocities of galaxies as a probe of cosmological models. We put particular emphasis on comparison of the peculiar velocity and density fields, focussing on the discrepancies between various recent analyses. We…

Astrophysics · Physics 2007-05-23 Michael A. Strauss , Michael Blanton

A hierarchical Bayesian model is applied to the Cosmicflows-3 catalog of galaxy distances in order to derive the peculiar velocity field and distribution of matter within $z \sim 0.054$. The model assumes the $\Lambda$CDM model within the…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 R. Graziani , H. M. Courtois , G. Lavaux , Y. Hoffman , R. B. Tully , Y. Copin , D. Pomarède

Optical flow refers to the visual motion observed between two consecutive images. Since the degree of freedom is typically much larger than the constraints imposed by the image observations, the straightforward formulation of optical flow…

Machine Learning · Statistics 2018-08-21 Jie Sun , Fernando J. Quevedo , Erik Bollt

We propose a method for deriving a dynamical lower bound on $\Omega$ from diverging flows in low-density regions, based on the fact that large outflows are not expected in a low-$\Omega$ universe. The velocities are assumed to be induced by…

Astrophysics · Physics 2009-10-22 Avishai Dekel , Martin Rees

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…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-04 Youness Ayaita , Maik Weber , Christof Wetterich

We investigate the reality of large-scale streaming on scales of up to 150 Mpc using the peculiar motions of galaxies in three directions. New R-band CCD photometry and spectroscopy for elliptical galaxies is used. The Fundamental Plane…

Astrophysics · Physics 2009-10-30 K. R. Müller , W. Freudling , R. Watkins , G. Wegner

The low-order kinematic moments of galaxies, namely bulk flow and shear, enables us to test whether theoretical models can accurately describe the evolution of the mass density field in the nearby Universe. We use the so-called etaMLE…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-05 Fei Qin , Cullan Howlett , Lister Staveley-Smith , Tao Hong

We study a variant of the mean curvature flow for closed, convex hypersurfaces where the normal velocity is a nonhomogeneous function of the principal curvatures. We show that if the initial hypersurface satisfies a certain pinching…

Analysis of PDEs · Mathematics 2020-01-09 Tim Espin

We present results for the bubble wall velocity and bubble wall thickness during a cosmological first-order phase transition in a condensed form. Our results are for minimal extensions of the Standard Model but in principle are applicable…

High Energy Physics - Phenomenology · Physics 2018-12-26 Glauber C. Dorsch , Stephan J. Huber , Thomas Konstandin

We study the gravitational influence of very large scale structures, as traced by clusters of galaxies, on the Local Group [LG] motion and the large scale flows. We derive from the distribution of Abell clusters within $300~$Mpc/h the…

Astrophysics · Physics 2007-05-23 R. Scaramella

We calculate the average volumetric flux versus pressure drop of bubbles moving in a single capillary tube with varying diameter, finding a square-root relation from mapping the flow equations onto that of a driven overdamped pendulum. The…

Fluid Dynamics · Physics 2013-08-09 Santanu Sinha , Alex Hansen , Dick Bedeaux , Signe Kjelstrup

The $\alpha$ turbulent viscosity formalism for accretion discs must be interpreted as a mean field theory. The extent to which the disc scale exceeds that of the turbulence determines the precision of the predicted luminosity $L_\nu$. The…

Astrophysics · Physics 2009-10-30 Eric G. Blackman

Using the 2MASS near-infrared photometry and high signal-to-noise HI 21-cm data from the Arecibo, Green Bank, Nancay, and Parkes telescopes, we calculate the redshift-independent distances and peculiar velocities of 2,018 bright inclined…

We study large scale structure in the cosmology of Coleman-de Luccia bubble collisions. Within a set of controlled approximations we calculate the effects on galaxy motion seen from inside a bubble which has undergone such a collision. We…

High Energy Physics - Theory · Physics 2014-11-20 Klaus Larjo , Thomas S. Levi

We present a simple method for measuring cosmological bulk flows from large redshift surveys, based on the apparent dimming or brightening of galaxies due to their peculiar motion. It is aimed at estimating bulk flows of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Adi Nusser , Enzo Branchini , Marc Davis

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…

Astrophysics · Physics 2009-10-30 R. Giovanelli , M. Haynes , J. Salzer , G. Wegner , L. da Costa , W. Freudling

We obtain estimates of all components of the velocity of a 3D rigid body moving in a viscous incompressible fluid without any symmetry restriction on the shape of the rigid body or the container. The estimates are in terms of suitable norms…

Analysis of PDEs · Mathematics 2023-04-25 Stathis Filippas , Alkis Tersenov