No-Hair Theorem

The No-Hair Theorem states that black holes can be completely described by just three properties: mass, electric charge, and angular momentum (spin). No matter what complex material or information falls into a black hole, it eventually disappears behind the event horizon, leaving only these three characteristics detectable from afar. This means all other details—the "hair"—are lost, making black holes remarkably simple objects in terms of their observable features. The theorem has important implications for understanding black hole behavior and the nature of information in the universe.