Is there a relationship between Black Holes and the Big Bang? As the question mentions, is there a relationship between the Big Bang and Black Holes? It appears the Big Bang is a ‘tacked on’ theory that doesn’t align with current theories (since we don’t know or observe dark energy, a mysterious force that explains why matter is accelerating outward). Is it possible that once we understand what happens inside black holes that it could explain our origin? If you can imagine what it’s like to someone inside a black hole event horizon, would they observe matter accelerating outward in a similar manner to our universe? Maybe it’s possible to view the singularity inside the event horizon as the exterior (by flipping the black hole inside out in a mathematical sense) - so to an observer inside the event horizon everything is accelerating outward). 
I come from a non-physics background, pls excuse my ignorance or seek further clarification on question. 
Links to simple, intuitive further reading appreciated. 
 A: Both exist in mathematical models using General Relativity, and both are successful in describing astrophysical observations up to now. That is where the similarity ends, because  the singularity at the beginning in the Big bang model is mathematically a different singularity than the ones modeling black holes.
An every day example is the singularities used to mathematically model a bathroom siphon, where the bath water will disappear into the hole, and the mathematics used to model an explosion. Both models  have a singularity ( i.e. an infinity at a (0,0,0) point) both use classical mechanics  and classical gravitation, but they are not the same type of singularity. This is because the data to be modeled in one case disappear into a hole, and in another a lot of matter appears from a small region.
The data that induced the Big Bang model resemble in the four dimensions of general relativity an explosion, whereas the data of black holes resemble a sink. 
The relationship is that the same mathematical theory, General relativity, can model with singularities both black holes and the  observable universe.
