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تسجيل مستخدم جديدGalaxy merging in MOND
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We present the results of N-body simulations of dissipationless galaxy merging in Modified Newtonian Dynamics (MOND). For comparison, we also studied Newtonian merging between galaxies embedded in dark matter halos, with internal dynamics equivalent to the MOND systems. We found that the merging timescales are significantly longer in MOND than in Newtonian gravity with dark matter, suggesting that observational evidence of rapid merging could be difficult to explain in MOND. However, when two galaxies eventually merge, the MOND merging end-product is hardly distinguishable from the final stellar distribution of an equivalent Newtonian merger with dark matter.
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The LCDM model is the most commonly admitted to describe our Universe. In spite of a great success with regard to the large scale structure formation, some problems are still unresolved at galactic scales. Alternative scenarios have to be explored su
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