The Universal Balloon
Why would Nature do otherwise?
Let's look at the balloon caused by the Singularity. The force of the explosion caused all the possible matter in the Universe to flow outwards since it was released...oh, from the prison of nothingness where it was boxed in so utterly. Ahem.
The force of the explosion carries all before it, the balloon moves into the vacuum of nothingness pushing all matter outwards. But smaller singularities form nearly immediately because of the density of matter, it tends to fall INTO EACH OTHER rather than repulsed away from each other. The energy to repulse starts when the first stars began to shine, the departing photon units have some force behind them.
I know this is bad physics, but bear with me for you are traveling through the thought patterns of a child, this is how I reasoned out things as a child.
It isn't one or two or twenty or fifty galaxies falling into each other, EVERY galaxy is falling into each other all the time. Each one has a gravitational pool. Each pool is as deep as each galaxy's mass can create on the surface of the space/time continuum. The great galaxies that are surrounded by hundreds or thousands of captive galaxies have deeeep indentations in the space/time balloon's surface. So deep, light from galaxies behind these monsters is multiplied and warped hugely, unimaginably hugely.
So, if all galaxies are falling INTO each other, how can the Universe be expanding rapidly and forever? What about red shift?