Question

What happen when two galaxies collapse​

Answer 1

Explanation:

Left alone, black holes lose mass due to 'Hawking radiation', so that their event horizons are slowly shrinking. ... But, the interior of the black hole, or its 'singularity' (the point at which all the black hole's matter is concentrated) has already reached the limit of its density and cannot 'collapse' any further.

Answer 2

Explanation:

When the galaxies collide, it causes vast clouds of hydrogen to collect and become compressed, which can trigger a series of gravitational collapses. A galaxy collision also causes a galaxy to age prematurely, since much of its gas is converted into stars