The Black Hole Saga

OK, here we go, mouth open up, here comes foot.Has there ever been documented proof of a Black Hole, Worm Hole, or Neutron Star? Were they not all created as theoretical elements due to a single or small group of complexities that could not be explained in other ways? I recognize that we have found pulsars and quasars but is there any proof that either phenomenon must be neutron based? Wasn’t the original reason we speculated the existence of these was because we did not think the universe was expanding as fast as it now turns out it actually is so wouldn’t the new realization that the universe may be expanding faster than originally thought negate the base reasoning behind why these phenomenon were first speculated into existence?I realize I am oversimplifying the physics behind the life cycles of stars but am I correct that black holes and Neutron Stars are in fact still theoretical entities that may or may not exist.

Thank you iar the links were very helpful. I don't see how we can determine the diameter of the center of mass that something of less density orbits around. We can see a star and see its orbit and infer from its trajectory the relative mass density of the object it orbits but from this distance away how can we be so sure as to the diameter of the central object. Does anyone know how the diameter of the more dense object is calculated if we can't see the object?Could there not be planets or moons 500 or 5000 times the size of our star? We know there are other stars hundreds of times the size of our Sun but how do we know that there can't be large planetoids that are the basis for what we see in the cosmos?Not debating the existence of the BH,WH,and NS, just wondering how we have proven their existence.