Thinking, Black Hole, General, Relativity, Physics.
summary, when we pass O, that is, when we cross the horizon, the space and time dimensions in the coordinate system (ξ, ω) are interchanged. Let’s not be mistaken: ξ remains ξ, and ω remains ω. But the former, which was space-like, becomes time-like. And the latter, which was time-like, becomes