Horizon Mass Theorem

TL;DR

The paper introduces the horizon mass theorem, stating that for all black holes, the horizon mass is always twice the irreducible mass observed at infinity, which is significant for understanding black hole physics.

Contribution

It presents a new theorem relating horizon mass to irreducible mass, expanding the theoretical framework of classical black hole properties.

Findings

Horizon mass is always twice the irreducible mass for all black holes.

The theorem applies to neutral, charged, and rotating black holes.

It is potentially the last general classical black hole theorem.

Abstract

A new theorem for black holes is found. It is called the horizon mass theorem. The horizon mass is the mass which cannot escape from the horizon of a black hole. For all black holes: neutral, charged or rotating, the horizon mass is always twice the irreducible mass observed at infinity. Previous theorems on black holes are: 1. the singularity theorem, 2. the area theorem, 3. the uniqueness theorem, 4. the positive energy theorem. The horizon mass theorem is possibly the last general theorem for classical black holes. It is crucial for understanding Hawking radiation and for investigating processes occurring near the horizon.