Results 1 to 10 of about 116,947 (262)
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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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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A Simple Model for Explaining Galaxy Rotation Curves
Galaxies, 2018 A new simple expression for the circular velocity of spiral galaxies is proposed and tested against HI Nearby Galaxy Survey (THINGS) data set. Its accuracy is compared with the one coming from MOND.
Aneta Wojnar +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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On the Counter-Rotation of Closed Time-like Curves [PDF]
Universe, 2022 While it is tempting to think of closed time-like curves (CTCs) around rotating bodies, such as a black hole, as being “caused” by the rotation of the source, Andréka et al.
Yuanyuan Duan +3 more
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Testing universal dark-matter caustic rings with galactic rotation curves
Physics Letters B, 2023 Infall of cold dark matter on a galaxy may result in caustic rings where the particle density is enhanced. They may be searched for as features in the galactic rotation curves.
Daniil Davydov, Sergey Troitsky
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Uncertainties in galaxy rotation curves [PDF]
Monthly Notices of the Royal Astronomical Society, 2021 ABSTRACT Assessing the likelihood that the rotation curve of a galaxy matches predictions from galaxy formation simulations requires that the uncertainties in the circular speed as a function of radius derived from the observational data be statistically robust. Few uncertainties presented in the literature meet this requirement. In this
Sellwood, J A +2 more
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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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HI Rotation Curves of Galaxies [PDF]
Symposium - International Astronomical Union, 1987 The observational evidence on the discrepancy between the mass distribution in galaxies derived from HI rotation curves and that derived from the distribution of light is reviewed. In the outer parts the discrepancy is such that in some galaxies there is at least three times as much dark matter as luminous matter.
SANCISI, R, VANALBADA, TS
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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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