Closed Timelike Curves

Closed Timelike Curves (CTCs) are theoretical paths through spacetime that loop back on themselves, allowing an object or observer to return to an earlier point in time along its own history. Think of it as a "shortcut" through spacetime that creates a sort of time loop. In physics, particularly in general relativity, certain solutions suggest such loops might exist under extreme conditions, like near rotating black holes. While fascinating, CTCs challenge our understanding of causality and have not been observed in reality; they remain a theoretical concept exploring the nature of time and spacetime.