How Does Time Dilation Affect Hawking Radiation Emission Near Black Holes?

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SUMMARY

The discussion centers on the relationship between time dilation and Hawking radiation emission near black holes. Participants clarify that Hawking radiation is not emitted solely at the event horizon, but rather that its emission probability decreases steeply with distance from the horizon. The heuristic model of virtual particle pairs, where one particle falls into the black hole while the other escapes, is acknowledged as a simplification that does not fully explain the complexities of quantum field theory involved in this process. The conversation emphasizes the need for a deeper understanding of quantum mechanics to accurately account for the factors influencing Hawking radiation.

PREREQUISITES
  • Understanding of Hawking radiation and black hole physics
  • Familiarity with quantum field theory concepts
  • Knowledge of gravitational tidal forces and potential gradients
  • Basic principles of time dilation in general relativity
NEXT STEPS
  • Study quantum field theory calculations related to black holes
  • Explore the implications of gravitational tidal forces on particle behavior
  • Research the effects of time dilation on particle emission near event horizons
  • Examine advanced models of Hawking radiation beyond heuristic explanations
USEFUL FOR

Physicists, astrophysicists, and students interested in black hole thermodynamics and quantum mechanics will benefit from this discussion, particularly those looking to deepen their understanding of Hawking radiation and its underlying principles.

mivanit
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So I realize that I'm probably wrong about this, but it seems to me that Hawking radiation cannot be emitted only at the event horizon. If we make the (albeit almost certainly wrong) assumption that the quantity of emitted particles is directly proportional to the potential for gravitational tidal forces between two particles, we find that the radiation emitted becomes constant and independent of the radius, which is not the case.
So here is my question: how can things like time dilation differences between the virtual particles, probabilities of the relative velocities of the particles, etc. be accounted for when calculating the amount of particle splits, and also do these splits occur in just a set region around the black hole, or are they just most probably very close to the black hole?

(sorry for any breaking of etiquette/bad english/bad physics, this is my first post and I'm not exactly very knowledgeable about physics or anything else)
 
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Well, your premise needs adjusting. A gravitational potential gradient
##\nabla \phi##, results in tidal forces.
 
I think that is what I meant, difference between forces on two particles due to gravity
(sorry for bad english)
 
mivanit said:
If we make the (albeit almost certainly wrong) assumption that the quantity of emitted particles is directly proportional to the potential for gravitational tidal forces between two particles, we find that the radiation emitted becomes constant and independent of the radius

I don't understand how you're reaching this result. (It's not really germane to the main question anyway, as you'll see below, but since you admit you're not very knowledgeable about physics, I'm curious how you arrived at this result.)

mivanit said:
how can things like time dilation differences between the virtual particles, probabilities of the relative velocities of the particles, etc. be accounted for when calculating the amount of particle splits, and also do these splits occur in just a set region around the black hole, or are they just most probably very close to the black hole?

The picture of Hawking radiation being produced by pairs of virtual particles separated by tidal gravity, so one falls into the hole while the other flies away, although it is commonly found in pop science presentations, is only a heuristic picture, and doesn't really work if you're trying to gain insight into why the radiation is emitted near the horizon (except for the obvious point that, for one of the particles to fall into the hole, the pair can't be produced too far from the horizon). Unfortunately, there isn't really a simple way to explain what's going on that works better than the heuristic picture for this (at least, I don't know of one); you would have to delve into the actual quantum field theory calculation, which is quite a bit more complicated than the heuristic picture suggests.

mivanit said:
do these splits occur in just a set region around the black hole, or are they just most probably very close to the black hole?

There is no hard "cutoff" to the region where Hawking radiation is emitted; like all quantum processes, it is really a matter of probability. But the probability of emission drops off very steeply as the distance from the horizon increases.
 
Thank you so much for helping me!
as for how I "arrived" at it being directly proportional, I just assumed it would be related for trying to calculate power. sorry for bad wording on my part.
After trying several possibilities for area where radiation occurs i figure out pretty fast it is not directly proportional to tidal force haha
thank you again so much!
 

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