گروه کیهان‌شناسی

Is there a fundamental acceleration scale in galaxies?

زهرا داوری

 دانشکده فیزیک دانشگاه صنعتی شریف

Abstract:  As we know, the mass discrepancy or missing mass problem has been found for many years in the galactic scale. Therefore, it seems that there is a need for a significant amount of non-luminous matter, i.e. the dark matter in galaxy system but up to now, no direct evidence of its existence has been found. One of the successful alternatives to the dark matter is Milgrom’s modified Newtonian dynamics (MOND) that could explain well the mass discrepancy problem in the galaxy without invoking dark matter. The MOND theory predicts a universal constant acceleration scale in the galaxy, below which the Newtonian dynamics is no longer valid. We analyzed 193 high-quality disk galaxies by using Bayesian inference and we concluded that the probability of the existence of a fundamental acceleration scale is essentially zero. However, there still exist evidence that rejects MOND as a fundamental theory and we conclude that a0 is of emergent nature.

یکشنبه 14 بهمن 1397، ساعت 15:00

دانشکده فیزیک، طبقه همکف کلاس فیزیک 1