Some descriptions show what a black hole might look like in a two-dimensional model of a three-dimensional universe.
Since childhood, Beltrão wanted to direct films and was fascinated by cinematographic and computer-generated three-dimensional universes.
Compared to the three-dimensional universe, the entire potential energy surface was upside-down.
Thus we are living in a universe only apparently spatially three-dimensional; infinitesimal but real dimensions lurk all about us.
If each three-dimensional universe exists then the existence of multiple three-dimensional universes suggests that the universe is four-dimensional.
Later - cooling, coalescing and changing over immense amounts of time and expansion - it had given rise to the cool, ordered, three-dimensional universe which people could see around them.
Gravity in the familiar three-dimensional universe obeys what is called the inverse square law.
Adding virtual lighting sources can give the resulting figures a sense of solidity and the scene the aura of a three-dimensional universe.
This is how we know that no perfect crystal exists anywhere in the three-dimensional universe.
So, we don't have to have one of our three-dimensional universe curved back on itself.