Backreaction of Hawking Radiation on a Gravitationally Collapsing Star I: Black Holes?

Understand

Particle creation leading to Hawking radiation is produced by the changing gravitational field of the collapsing star.

• The two main initial conditions in the far past placed on the quantum field from which particles arise, are the Hartle Hawking vacuum and the Unruh vacuum.
• The former leads to a time symmetric thermal bath of radiation, while the latter to a flux of radiation coming out of the collapsing star.
• The energy of Hawking radiation in the interior of the collapsing star is negative and equal in magnitude to its value at future infinity.