Outcome of competition between bar propeller effects and continued dark-matter accretion onto Sgr A*

Ascertain whether the future evolution of the Milky Way will be dominated by the rapidly reversing Galactic bar pattern speed (propeller effect) or by ongoing dark-matter accretion onto Sgr A*, specifically whether the bar’s evolution will suppress or prevent continued dark-matter inflow onto the supermassive black hole.

Background

Projecting current trends, the authors argue the bar’s pattern speed could become strongly negative, potentially inducing a propeller effect that dramatically affects the Galactic disk and might even halt dark-matter accretion onto Sgr A*. They highlight the unresolved question of which process will dominate the Galaxy’s near-future evolution.

They explicitly state that further work is required to determine the winner of this competition.