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Computation of the Semiclassical Outflux Emerging from a Collapsing Spherical Null Shell.
1Technion, Department of Physics, Haifa 32000, Israel.
Physical Review Letters
|July 31, 2025
Summary
This study analyzes quantum scalar field behavior near a collapsing black hole shell. The energy outflux density evolves gradually, not solely from the shell, avoiding significant backreaction effects.
Area of Science:
- Theoretical Physics
- Quantum Field Theory
- General Relativity
Background:
- Investigates quantum fields in curved spacetime.
- Examines black hole formation from collapsing null shells.
- Utilizes the "in" vacuum state for the quantum field.
Purpose of the Study:
- Analyze vacuum polarization and energy outflux density.
- Derive closed-form analytical expressions for these quantities.
- Understand the emission mechanism of Hawking radiation.
Main Methods:
- Semiclassical approximation framework.
- Point-splitting method for regularization.
- Analysis of a minimally coupled, massless quantum scalar field.
Main Results:
- Derived analytical expressions for vacuum polarization and energy outflux.
- Showed energy outflux density vanishes as the shell approaches the event horizon.
- Demonstrated gradual evolution of outflux along late-time geodesics.
Conclusions:
- Hawking radiation outflux evolves gradually in the strong-field region.
- Confirms that emission is not solely from the collapsing shell.
- Avoids significant backreaction effects on the black hole spacetime.
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