arXiv:2403.03227v1 Announce Type: new
Abstract: In recent years, there has been an increase in the number of papers regarding general-relativistic explanations for the dark matter phenomena in disc galaxies. The main focus of this scientific discussion is whether a previously unexamined relativistic dragging vortex could support flat rotation curves, with various research groups taking different stances on its feasibility. In this paper, we discuss the different points of view by placing the various arguments within a general theoretical context. We explicitly state the conceptual assumptions, and indicate what we believe to be the correct interpretation for the physical quantities of interest. We show how the dragging conjecture fails under certain hypotheses, and discuss the flaws of the most common dragging models: the linearised gravitomagnetic description and the one of Balasin&Grumiller. On the other hand, we illustrate how to avoid failure scenarios for the conjecture, emphasizing the features for a physically reasonable disc galaxy dragging model. In particular, we stress that the non-linearities of the Einstein Equations must play an essential role in generating what we define as “pseudo-solitonic” solutions — the only non-trivial physically viable solutions for the class of models considered. Furthermore, the dragging vortex is proven to show important contributions to the gravitational lensing in these models, thus providing an ulterior measure of its relevance. Moreover, by qualitatively exploring these pseudo-solitonic solutions, we find that a dragging speed of just a few kilometers per second would be enough to explain a non-negligible fraction of the galactic dark matter. Finally, we propose and analyse the feasibility of three independent measurements which could be carried out to detect the presence of dragging vortices in disc galaxies.
Conclusion:
General-relativistic explanations for the dark matter phenomena in disc galaxies have been a topic of increasing interest in recent years. The feasibility of a dragging vortex as a support for flat rotation curves has been a subject of debate among research groups. This paper discusses the different points of view and places the arguments within a general theoretical context. It identifies the flaws in the most common dragging models and proposes a physically reasonable model that avoids failure scenarios. The dragging vortex is shown to have important contributions to gravitational lensing, further highlighting its relevance. The paper also suggests that a dragging speed of just a few kilometers per second could explain a non-negligible fraction of the galactic dark matter. Finally, it proposes three independent measurements to detect the presence of dragging vortices in disc galaxies.
Future Roadmap:
- Further Research: Given the ongoing debate and differing viewpoints, further research is needed to explore and refine the dragging vortex model. This includes investigating the non-linearities of the Einstein Equations and their role in generating physically viable solutions.
- Experimental Validation: The feasibility of the proposed dragging vortex model and its contribution to dark matter can be tested through three independent measurements. These measurements should be conducted to provide empirical evidence for the existence and properties of dragging vortices in disc galaxies.
- Challenges: One challenge that researchers may face is obtaining accurate and reliable measurements of dragging speeds and their effects on gravitational lensing. Additionally, the identification and quantification of the fraction of dark matter explained by the dragging vortex model may require advanced data analysis techniques.
- Opportunities: The successful validation of the dragging vortex model and its role in explaining dark matter could lead to a deeper understanding of the nature of dark matter and its implications for the laws of gravity. It may also open up new avenues for studying and manipulating gravitational fields.