Why does surface area of an Event Horizon increase?

In summary, Stephen Hawking came to know of a study that stated that surface area of an event horizon increases. So he said that since area has increased Entropy also had increased.
  • #1
avito009
184
4
Stephen hawking came to know of a study that stated that surface area of an event horizon increases. So he said that since area has increased Entropy also had increased.

But why does surface area of an Event Horizon increase?
 
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  • #2
That's a theorem (proven by Hawking). Are you asking about the proof of the theorem?
 
  • #3
avito009 said:
Stephen hawking came to know of a study that stated that surface area of an event horizon increases. So he said that since area has increased Entropy also had increased.

But why does surface area of an Event Horizon increase?
Surface area depends on radius. Radius is proportional to mass.
 
  • #4
avito009 said:
Stephen hawking came to know of a study that stated that surface area of an event horizon increases. So he said that since area has increased Entropy also had increased.

But why does surface area of an Event Horizon increase?
It increases due to the black hole pulling more material into itself, therefore trapping it in the event horizon, enlarging it. The material would get trapped into an 'orbit' around the black hole. Never able to escape, neither get pulled into the black hole.
 
  • #5
The event horizon is simply the distance from the center of the black hole where the curvature of space becomes so great that there are no paths through spacetime that can lead you back out of it. Just outside the event horizon the curvature of space is still extreme and the only paths available that don't take you into the black hole are the ones where your velocity is either the speed of light or very close to it. Since mass causes curvature of space, a more massive black hole will curve space more, causing the event horizon to be located further out, which means that the "surface" is larger.
 
  • #6
avito009 said:
But why does surface area of an Event Horizon increase?

The surface area of a black hole is given by ##4\pi{R}^2## where ##R## is the Schwarzschild radius. The schwarzschild radius increases as mass falls into the black hole, so the area also does.
 
  • #7
EpicAll Rounder said:
It increases due to the black hole pulling more material into itself
yes.
therefore trapping it in the event horizon, enlarging it. The material would get trapped into an 'orbit' around the black hole. Never able to escape, neither get pulled into the black hole.
That's not right. The trapped material falls through the event horizon and into the central singularity rather quickly; it's just that an observer outside the event horizon doesn't get to see it.

This question has been the subject of many threads over in the relativity forum, so you may want to try searching the topic there.
 

1. What is an event horizon?

An event horizon is a boundary in space surrounding a black hole, beyond which no matter or energy can escape due to the intense gravitational pull.

2. How does the surface area of an event horizon increase?

The surface area of an event horizon increases as a result of the black hole's mass increasing. This is because the event horizon is directly related to the mass of the black hole, as described by the equation A = 16πG²M²/c⁴, where A is the surface area, G is the gravitational constant, M is the mass of the black hole, and c is the speed of light.

3. Why does the surface area of an event horizon matter?

The surface area of an event horizon is important because it is directly related to the amount of matter and energy that can be consumed by the black hole. The larger the surface area, the more matter and energy the black hole can consume, making it more powerful.

4. Is the increase in surface area of an event horizon linear?

No, the increase in surface area of an event horizon is not linear. As the mass of the black hole increases, the surface area increases at a decreasing rate. This means that as the black hole grows, it takes in more mass and energy at a slower rate.

5. Can the surface area of an event horizon decrease?

No, the surface area of an event horizon can only increase. This is because the surface area is directly related to the mass of the black hole, and according to the laws of physics, mass cannot be destroyed. However, the rate of increase may slow down as the black hole reaches its maximum potential mass.

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