A black hole is so dense that a sphere around it called the event horizon has a greater escape velocity than the speed of light, making it black. So why do astronomers think that there is anything weird (or lack of anything Inc space) inside the event horizon. Why isn't simple the limit to where light can escape and in the middle of event horizon (which physically isnt a surface) is just a hyper dense ball of the matter that's been sucked in and can't escape just like light. Why is it thought that the laws of physics don't exist in the event horizon?
Answer
For large enough black holes, space is still weakly curved at the event horizon, so of course we should expect that normal physics still exists there. An infalling observer wouldn't experience anything out of the ordinary when crossing an event horizon.
What is true is that for an outside observer, it's impossible to probe what's happening inside the event horizon of a black hole. (The best you can do is wait a long time and collect the outgoing Hawking radiation.) So from the point of view of such an observer, you can't really tell the difference between living in a world where spacetime keeps going across the horizon, or living in a world where space just ends there and some radiation emerges. This might be the sort of idea your teacher was getting at. You might want to look up "black hole complementarity" to learn more.
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