The future Milky Way and Andromeda galaxy merger

TL;DR

This paper uses numerical simulations to study the future collision and merger of the Milky Way and Andromeda galaxies, focusing on the impact of initial conditions and the dynamics of central black holes.

Contribution

It provides new insights into the role of indeterminacy in galaxy merger timing and black hole dynamics through detailed simulations.

Findings

Merger timing is highly sensitive to initial velocities.

Black holes' relative motion during merger was analyzed.

Simulation results highlight uncertainties in predicting exact merger timelines.

Abstract

According to our current knowledge about physical and dynamical properties of the Milky Way-M31 system, it seems likely that these two galaxies will collide and eventually merge in a time very sensitive to initial conditions. Using the HiGPUs code, we have performed several numerical simulations to study the dynamics of the system, trying to define the role of indeterminacy in the present day observed relative velocities of the two galaxies and the time of the merger. At the same time, we have followed the dynamics of the two massive black holes sitting in the galactic centers, to check (within the space and time resolution limits of our simulation) their relative motion upon the completion of the galaxies merger process.