Title: Properties Of Black Holes
Course: Relativity > Section: Module 36: Properties Of Black Holes

Properties of Black Holes

Black holes can be classified into different types based on their mass:

1. Stellar Black Holes:
  - Formed by the gravitational collapse of massive stars. They typically have a mass between about 3 to 20 times that of the Sun.
2. Supermassive Black Holes:
  - Found at the centers of most galaxies, including our Milky Way. These giants can have masses ranging from millions to billions of times that of the Sun. Their formation is still an area of active research, but they may grow by merging with other black holes and absorbing surrounding stars and gas.
3. Intermediate Black Holes:
  - These may exist with masses between stellar and supermassive black holes, but their existence is still debated and not well understood.
4. Primordial Black Holes:
  - Hypothetical black holes that may have formed soon after the Big Bang due to density fluctuations in the early universe.

Key Properties of Black Holes

- Singularity:
  - The core of the black hole where mass is thought to be infinitely dense.
- Event Horizon:
  - The boundary surrounding a black hole beyond which no light or information can escape. It is not a physical surface but rather a point of no return.
- Accretion Disk:
  - Matter that spirals into a black hole often forms a disk around it, heating up and emitting radiation in the process. This can give off significant amounts of energy, making black holes detectable by telescopes.

The Concept of the Event Horizon