Blackhole radiation v Second Law

Click For Summary
SUMMARY

The discussion centers on the apparent contradiction between Hawking radiation and the Second Law of black hole dynamics, which states that the area of the event horizon cannot decrease. It is established that Hawking radiation leads to black hole evaporation, resulting in a decrease in both mass and event horizon area over time, thus superseding the traditional interpretation of the Second Law. The conversation also touches on the implications of free fall versus static conditions on event horizon size and the appropriateness of using π for calculating spherical areas in warped spacetime.

PREREQUISITES
  • Understanding of Hawking radiation and black hole thermodynamics
  • Familiarity with the Second Law of black hole dynamics
  • Knowledge of spacetime geometry and Killing Vectors
  • Basic principles of general relativity
NEXT STEPS
  • Research the implications of Hawking radiation on black hole mass and area
  • Study the Second Law of black hole dynamics in detail
  • Explore the concept of Killing Vectors in general relativity
  • Investigate the effects of spacetime curvature on geometric calculations
USEFUL FOR

The discussion is beneficial for physicists, cosmologists, and students of theoretical physics interested in black hole dynamics, thermodynamics, and general relativity.

ash99
Messages
1
Reaction score
0
Can someone help me on this: Hawking Bernstein radiation can cause a BH to evaporate. The second law of BH dynamics says that the area of the event horizon cannot decrease. Isn't this a contradiction? Also when considering the size of the event horizon, is it different depending on wheather one is in free fall or static. Finally is it ok to use PI to calculate spherical area in heavily warped space?
If the answers involve Killing Vectors, I'll need help with those as well.
 
Astronomy news on Phys.org
The Second Law

The horizon area is, assuming the weak energy condition, a non-decreasing function of time,

This "law" was superseded by Hawking's discovery that black holes radiate, which causes both the black hole's mass and the area of its horizon to decrease over time.

Above from:

http://en.wikipedia.org/wiki/Black_hole_thermodynamics
 
Last edited:

Similar threads

High School Can Black Holes Be Annihilated?
  • · Replies 6 ·
Replies
6
Views
7K
Graduate What are the effects of Hawking radiation on black holes?
  • · Replies 1 ·
Replies
1
Views
4K
Undergrad I don't see how a black hole's event horizon can be crossed
  • · Replies 73 ·
3
Replies
73
Views
4K
Undergrad Falling through the event horizon of an evaporating black hole
  • · Replies 51 ·
2
Replies
51
Views
6K
Graduate Origin of BH Entropy & Info Missing Puzzle Resolution
  • · Replies 6 ·
Replies
6
Views
2K
Graduate Hawking Radiation Inside a Black Hole: Theory & Possibilities
  • · Replies 7 ·
Replies
7
Views
2K
Graduate How Does Hawking Radiation Affect Black Hole Energy Loss?
  • · Replies 4 ·
Replies
4
Views
5K
Graduate Penrose diagram of black hole with a changing event horizon
  • · Replies 3 ·
Replies
3
Views
4K
Graduate Why spacetime quantization does not prevent blackhole formation?
  • · Replies 16 ·
Replies
16
Views
4K
High School Question about the Entropy of a Black Hole Singularity
  • · Replies 17 ·
Replies
17
Views
4K