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Mass of a black hole firewall
M A Abramowicz1, W Kluźniak2, J-P Lasota3
1Copernicus Astronomical Center, ul. Bartycka 18, 00-716 Warszawa, Poland and Department of Physics, University of Gothenburg, SE-412-96 Göteborg, Sweden.
Physical Review Letters
|March 25, 2014
Summary
Planck density firewalls near black holes are excluded by Einstein's equations. Astrophysical black holes have firewall densities vastly smaller than Planck density, challenging previous theories.
Area of Science:
- Theoretical physics
- Black hole thermodynamics
- Quantum gravity
Background:
- The firewall paradox suggests a high-energy barrier at black hole event horizons due to entangled Hawking radiation.
- Previous hypotheses proposed Planck density firewalls, posing a challenge to black hole information paradox solutions.
Purpose of the Study:
- To investigate the physical possibility of Planck density firewalls near black hole event horizons.
- To re-evaluate firewall formation using Einstein's field equations.
Main Methods:
- Application of Einstein's field equations to Schwarzschild black holes.
- Calculation of upper bounds for firewall surface density.
Main Results:
- Planck density firewalls are mathematically excluded for black holes with mass exceeding the Planck mass.
- An upper limit of 1/(8πM) for firewall surface density was derived for a Schwarzschild black hole of mass M.
- For astrophysical black holes, the calculated firewall density is over 30 orders of magnitude smaller than Planck density.
Conclusions:
- The existence of Planck density firewalls is inconsistent with established gravitational theory for massive black holes.
- The derived upper limit suggests that firewalls, if they exist, are significantly less dense than previously theorized, potentially resolving paradoxes.
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