Results 11 to 20 of about 116,947 (262)
Gravitational orbits in the expanding Universe revisited
Frontiers in Astronomy and Space Sciences, 2023 Modified Newtonian equations for gravitational orbits in the expanding Universe indicate that local gravitationally bounded systems like galaxies and planetary systems are unaffected by the expansion of the Universe.
Václav Vavryčuk
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Dark Baryons and Rotation Curves [PDF]
The Astrophysical Journal, 1997 The best measured rotation curve for any galaxy is that of the dwarf spiralXXXX DDO 154, which extends out to about 20 disk scale lengths. It provides an ideal laboratory for testing the universal density profile prediction from high resolution numerical simulations of hierarchical clustering in cold dark matter dominated cosmological models.
Burkert, A., Silk, J.
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Debate on the Physics of Galactic Rotation and the Existence of Dark Matter
Galaxies, 2020 This Special Issue was motivated by the disparate explanations of galactic dynamics promulgated by different philosophical camps [...]
Anne M. Hofmeister, Robert E. Criss
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Galaxy Rotation Curve Fitting Using Machine Learning Tools
Universe, 2023 Galaxy rotation curve (RC) fitting is an important technique which allows the placement of constraints on different kinds of dark matter (DM) halo models. In the case of non-phenomenological DM profiles with no analytic expressions, the art of finding RC
Carlos R. Argüelles, Santiago Collazo
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Rotation Curves of 967 Spiral Galaxies [PDF]
The Astrophysical Journal Supplement Series, 1995 We present the rotation curves (RCs) of 967 spiral galaxies, obtained by folding and deprojecting the raw optical data by Mathewson et al. (1992). Out of these, we have identified 80 excellent RCs and 820 fair RCs. The 80 excellent RCs are smooth, symmetric, have negligible rms internal error, extend to at least the optical radius, and have high and ...
Persic, M., Salucci, P.
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Rotation Curve of the Galaxy [PDF]
Publications of the Astronomical Society of Japan, 1997 Reanalyzing the galactic HI survey data with two methods which make use of the geometry of the galactic disk, we explore the outer rotation curve. In addition to the derivation of the outer rotation curve, we investigate their uncertainties, which have not been established previously.
Mareki Honma, Yoshiaki Sofue
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Nonstandard Approach to Gravity for the Dark Sector of the Universe
Entropy, 2013 We summarize the present state of research on the darkon fluid as a model for the dark sector of the Universe. Nonrelativistic massless particles are introduced as a realization of the Galilei group in an enlarged phase space.
Wojtek J. Zakrzewski, Peter C. Stichel
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Thermodynamic Constraints on the Non-Baryonic Dark Matter Gas Composing Galactic Halos
Galaxies, 2020 To explain rotation curves of spiral galaxies through Newtonian orbital models, massive halos of non-baryonic dark matter (NBDM) are commonly invoked. The postulated properties are that NBDM interacts gravitationally with baryonic matter, yet negligibly ...
Anne M. Hofmeister
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Dark matter fluid constraints from galaxy rotation curves
European Physical Journal C: Particles and Fields, 2023 Galaxy rotation curves are considered to be convincing evidence for dark matter or some dynamically equivalent alternative mechanism. Starting only from the rotation curve data, we present a model independent approach of testing a general hypothesis that
Dalibor Perković, Hrvoje Štefančić
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On Filaments, Prolate Halos and Rotation Curves [PDF]
The 1st Electronic Conference on Universe, 2021 Abstract We propose a simple geometrical mechanism for the flattening of galactic rotation curves, the local compression of field lines around their planes induced either by the presence of thin string-like objects at the centers of galaxies or by elongated dark-matter halos, and elaborate on its possible role in Nature.
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