What is a black hole? How can we understand it?
What do we mean by black hole?
Why are black holes black? What is beyond a black hole? What is an event horizon of a black hole? Why can't we find a black hole? Are black holes and singularities related? What is the event horizon in a black hole? What happens to matter when it enters a black hole? Are black holes singularities? Why do black holes have gravity? Is there a singularity inside the event horizon of a black hole? How do we know we are not living in a black hole? Where does matter go after falling into a black hole? How are black holes formed? Does dark matter affect black holes? What does "the singularity in a black hole is a future moment in time" mean for someone inside the event horizon? How black holes are formed? Does something that goes into a black hole come out the other side? Are black holes like sink holes? Are black holes portals? Do all galaxies have a black hole? What is the difference between black holes and white holes? Is there any relation between black holes and wormholes? What happens when someone enters the black hole? Why do black holes change? What happens to matter when it gets sucked by a black hole? Can we travel through black holes? Could the singularity of a black hole be a graviton? Which equation in general relativity predicted the existence of black-holes ? Is it possible to think of black holes as having no spacetime inside the event-horizon? Can we kill a black hole?