[Melas]

In an expanding universe, celestial objects are continually moving further apart from one another as they move apart from their common origin. If all objects in the universe were falling down a giant black hole, by necessity, all objects in the universe would be moving closer together as they neared their common destination.

[Ernest_at_the_Beach]

In an expanding universe,

That theory is beginning to have a problem as it is based on Hubble's observation of Red Shift and his conclusion and explanation of what was causing it!

One of his students has been doing some work:

Seeing Red: Intrinsic redshifts, stable universe

Somewhat related thread :

Giant solar waves spew more energy than 10 bn atom bombs