Virial theorem in clusters of galaxies with MOND

López-Corredoira, Martín; Betancort-Rijo, J.; Scarpa, Riccardo; Chrobáková, Ž.

doi:10.1093/mnras/stac3117

Cited by 6 publications

(5 citation statements)

References 76 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Galaxy clusters have been posing some tension in that a factor of two in mass appears to be missing but can be accounted for in MOND if sterile neutrinos exist (e.g. Banik & Zhao 2022 and references therein) and also if appropriate boundary conditions are taken into account for these large structures (López-Corredoira et al 2022). The prominent Bullet cluster of galaxies has been used as a default object for the proof of the existence of dark matter particles.…”

Section: Discussionmentioning

confidence: 99%

Asymmetrical tidal tails of open star clusters: stars crossing their cluster’s práh† challenge Newtonian gravitation

Kroupa

Jeřabková

Thies

et al. 2022

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

After their birth a significant fraction of all stars pass through the tidal threshold (práh) of their cluster of origin into the classical tidal tails. The asymmetry between the number of stars in the leading and trailing tails tests gravitational theory. All five open clusters with tail data (Hyades, Praesepe, Coma Berenices, COIN-Gaia 13, NGC 752) have visibly more stars within $d_{\rm cl}\approx 50\,{\rm pc}$ of their centre in their leading than their trailing tail. Using the Jerabkova-compact-convergent-point (CCP) method, the extended tails have been mapped out for four nearby 600–2000 Myr old open clusters to $d_{\rm cl} > 50\,{\rm pc}$. These are on near-circular Galactocentric orbits, a formula for estimating the orbital eccentricity of an open cluster being derived. Applying the Phantom of Ramses code to this problem in Newtonian gravitation the tails are near-symmetrical. In Milgromian dynamics (MOND), the asymmetry reaches the observed values for 50 < dcl/pc < 200 being maximal near peri-galacticon, and can slightly invert near apo-galacticon, and the Küpper epicyclic overdensities are asymmetrically spaced. Clusters on circular orbits develop orbital eccentricity due to the asymmetrical spill-out, therewith spinning up opposite to their orbital angular momentum. This positive dynamical feedback suggests Milgromian open clusters to demise rapidly as their orbital eccentricity keeps increasing. Future work is necessary to better delineate the tidal tails around open clusters of different ages and to develop a Milgromian direct n-body code.

show abstract

Section: Discussionmentioning

confidence: 99%

Asymmetrical tidal tails of open star clusters: stars crossing their cluster’s práh† challenge Newtonian gravitation

Kroupa

Jeřabková

Thies

et al. 2022

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

show abstract

“…Galaxy clusters have been posing some tension in that a factor of two in mass appears to be missing but can be accounted for in MOND if sterile neutrinos exist (e.g., Banik & Zhao 2022 and references therein) and also if appropriate boundary conditions are taken into account for these large structures (López-Corredoira et al 2022). The prominent Bullet cluster of galaxies has been used as a default object for proof of the existence of dark matter particles.…”

Section: Discussionmentioning

confidence: 99%

Open Star Clusters and Their Asymmetrical Tidal Tails

Kroupa,

Pflamm-Altenburg,

Mazurenko

et al. 2024

ApJ

View full text Add to dashboard Cite

Stars that evaporate from their star cluster by the energy equipartition process end up in either a leading or a trailing tidal tail. In Newtonian gravitation and for open star clusters in the solar vicinity, the tidal threshold, or práh, for escape is symmetrical, such that the leading and trailing tails are equally populated. The data from six independent teams that applied the convergent point method to map out the tidal tails of four open clusters (the Hyades, Praesepe, Coma Berenices, and COIN-Gaia 13) using Gaia DR2 and DR3 are here applied to test for the expected symmetry. All tidal tails contain more stars in the leading tail. The combined confidence amounts to an 8σ falsification of the práh symmetry. The same test using Milgromian dynamics leads to consistency with the data. More effort needs to be exerted on this matter, but the data indicate with high confidence that the tidal práh of an open star cluster is asymmetrical, with the corresponding confidence that Newtonian gravitation is falsified. Open star clusters depopulate more rapidly in Milgromian than in Newtonian dynamics, and the COIN-Gaia 13 cluster is here found to be nearly completely dissolved. In view of these results, the wide-binary star test and the finding of a Keplerian Galactic rotation curve are briefly discussed.

show abstract

“…Notably, dispersion was observed within each group of galaxies based on their type. The recent investigation of galaxy clusters, on the other, shows that they less prominently demonstrate the effect of 'dark matter' [14]. At the same time, another investigation [15] showed that their shape is closer to a sphere than previously mentioned.…”

Section: Introductionmentioning

confidence: 87%

Dark matter effects explanation with the torsion in the Minkowski space

Romanets

2024

Class. Quantum Grav.

View full text Add to dashboard Cite

Introduction: Investigating rotation curves and the Tully-Fisher ratio within galaxies represents a central theme of extensive research and scientific interest. Despite several theoretical models, a comprehensive explanation of the observed correlation between galaxy types and their rotation curves remains elusive. This study endeavors to bridge this knowledge gap by delving into the discernible connection between the presence of dark matter and galaxy classification.Theoretical background: By meticulously examining the gravitational field's dependency on its source's point symmetry, we introduce a novel theoretical framework that offers a coherent rationale for these empirical findings. Results: Our proposed model explains the appearance of dark matter as a direct consequence of the reduction of point symmetry in gravitational systems. Neither arbitrary systems with a high mass density nor a perfectly spherically symmetric mass distribution give the observable effects of dark matter. Special attention was paid to the axial symmetry scenario as a reasonable approach for modeling the mass distribution in most galaxies. We thoroughly analyzed, showing strong agreement with experimental observations for dwarf, Sb, and Scd galaxies. Conclusion: Thus, our study provides a compelling theoretical foundation for elucidating the intricate interplay between galaxy types, rotation curves, and the presence of dark matter, shedding new light on the dynamics of the cosmos.

show abstract

Virial theorem in clusters of galaxies with MOND

Cited by 6 publications

References 76 publications

Asymmetrical tidal tails of open star clusters: stars crossing their cluster’s práh† challenge Newtonian gravitation

Asymmetrical tidal tails of open star clusters: stars crossing their cluster’s práh† challenge Newtonian gravitation

Open Star Clusters and Their Asymmetrical Tidal Tails

Dark matter effects explanation with the torsion in the Minkowski space

Contact Info

Product

Resources

About