Results 1 to 10 of about 10,600 (149)
Measuring the Hubble Constant through the Galaxy Pairwise Peculiar Velocity
The Astrophysical Journal LettersThe Hubble constant H _0 , the current expansion rate of the Universe, is one of the most important parameters in cosmology. The cosmic expansion regulates the mutually approaching motion of a pair of celestial objects due to their gravity.
Wangzheng Zhang +4 more
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Universe, 2021 According to the Cosmological Principle, the Universe is isotropic and no preferred direction would be seen by an observer that might be stationary with respect to the expanding cosmic fluid.
Ashok K. Singal
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Speed Measurement in an Accomoving Reference System
East European Journal of Physics, 2020 A method of direct measurement of the observer's velocity (peculiar velocity) relative to the accompanying reference system is proposed and investigated. To measure peculiar velocity, it is proposed to use the measurement of stellar light aberration.
Volodymyr М. Svishch
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Relativistic approach to the kinematics of large-scale peculiar motions
European Physical Journal C: Particles and Fields, 2020 We consider the linear kinematics of large-scale peculiar motions in a perturbed Friedmann universe. In so doing, we take the viewpoint of the “real” observers that move along with the peculiar flow, relative to the smooth Hubble expansion.
Eleni Tsaprazi, Christos G. Tsagas
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The deceleration parameter in ‘tilted’ universes: generalising the Friedmann background
European Physical Journal C: Particles and Fields, 2022 Large-scale bulk peculiar motions introduce a characteristic length scale, inside which the local kinematics are dominated by peculiar-velocity perturbations rather than by the background Hubble expansion. Regions smaller than the aforementioned critical
Christos G. Tsagas
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On the Distances to the X-Ray Binaries Cygnus X-3 and GRS 1915+105
The Astrophysical Journal, 2023 In this paper we significantly improve estimates of distance to the X-ray binary systems Cyg X-3 and GRS 1915+105. We report a highly accurate trigonometric parallax measurement for Cyg X-3 using the Very Long Baseline Array at 43 GHz, placing the source
M. J. Reid, J. C. A. Miller-Jones
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Review of Single Bubble Motion Characteristics Rising in Viscoelastic Liquids
International Journal of Chemical Engineering, 2021 The emphasis of this review is to discuss three peculiar phenomena of bubbles rising in viscoelastic fluids, namely, the formation of a cusp, negative wake, and velocity jump discontinuity, and to highlight the possible future directions of the subject ...
Wei Wang
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Discovery of the Tadpole Molecular Cloud near the Galactic Nucleus
The Astrophysical Journal, 2023 In this paper, we report the discovery of an isolated, peculiar compact cloud with a steep velocity gradient at 2.′6 northwest of Sgr A*. This “Tadpole” molecular cloud is unique owing to its characteristic head-tail structure in the position–velocity ...
Miyuki Kaneko +6 more
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Geosciences, 2022 Velocity is one of the most important parameters to evaluate the damaging potential of a mass movement, but its assessment, especially for extremely rapid landslides, is a complex task.
Antonella Marinelli +5 more
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Voids in the Cosmic Web as a probe of dark energy
Condensed Matter Physics, 2017 The formation of large voids in the Cosmic Web from the initial adiabatic cosmological perturbations of space-time metric, density and velocity of matter is investigated in cosmological model with the dynamical dark energy accelerating expansion of the ...
B. Novosyadlyj, M. Tsizh
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