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Collisional Penrose process in black hole ergospheres can extract immense energy. This process may enhance dark matter annihilation near supermassive black holes, offering new research avenues.

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Area of Science:

  • Astrophysics
  • General Relativity
  • Particle Physics

Background:

  • The Kerr metric describes rotating black holes, featuring an ergosphere outside the event horizon.
  • Roger Penrose discovered that particles in the ergosphere can have negative energy, enabling mass and angular momentum extraction from black holes.

Purpose of the Study:

  • To review the history and applications of the Penrose process.
  • To explore the astrophysical implications of particle collisions within the ergosphere.
  • To investigate the potential of the collisional Penrose process to enhance dark matter annihilation.

Main Methods:

  • Review of theoretical frameworks for energy extraction from rotating black holes.
  • Analysis of particle dynamics and collisions within the ergosphere.
  • Modeling of dark matter annihilation enhancement in supermassive black hole environments.

Main Results:

  • Single particle decay is inefficient, but particle collisions can yield arbitrarily high center-of-mass energies.
  • High-energy particles can escape the ergosphere with significant efficiency.
  • The collisional Penrose process shows potential for boosting dark matter annihilation rates.

Conclusions:

  • The collisional Penrose process offers a mechanism for efficient energy extraction from black holes.
  • This process could serve as a probe for high-energy physics and general relativity.
  • Enhanced dark matter annihilation near supermassive black holes is a promising astrophysical application.