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Galaxy rotation curves via conformal factors [PDF]
European Physical Journal C: Particles and Fields, 2018 We propose a new formula to explain circular velocity profiles of spiral galaxies obtained from the Starobinsky model in the Palatini formalism. It is based on the assumption that the gravity can be described by two conformally related metrics: one of ...
Ciprian A. Sporea +2 more
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Towards the Explanation of Flatness of Galaxies Rotation Curves
Universe, 2022 We suggest a new explanation of the flatness of galaxies rotation curves without invoking dark matter. For this purpose, a new gravitational tensor field is introduced in addition to the metric tensor.
Sergey A. Larin
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Effects of Higher Order Retarded Gravity
Universe, 2021 In a recent paper, we have a shown that the flattening of galactic rotation curves can be explained by retardation. However, this will rely on a temporal change of galactic mass.
Asher Yahalom
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Density Profiles of 51 Galaxies from Parameter-Free Inverse Models of Their Measured Rotation Curves
Galaxies, 2020 Spiral galaxies and their rotation curves have key characteristics of differentially spinning objects. Oblate spheroid shapes are a consequence of spin and reasonably describe galaxies, indicating that their matter is distributed in gravitationally ...
Robert E. Criss, Anne M. Hofmeister
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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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Debated Models for Galactic Rotation Curves: A Review and Mathematical Assessment
Galaxies, 2020 Proposed explanations of galactic rotation curves (RC = tangential velocity vs. equatorial radius, determined from Doppler measurements) involve dramatically different assumptions.
Anne M. Hofmeister, Robert E. Criss
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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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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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