Entropy & Black Holes: The Relationship Between Area & Information

In summary: This effect is proportional to the mass of the object and is independent of any information that may be present on the object before it goes in.
  • #1
kurious
641
0
A blank sheet of paper falling into a black hole would increase the area of the event horizon and the increase in area would be associated with an increase in the entropy of the black hole.If I cut away bits of a heavier sheet to write some sentences,and the cut sheet had the same mass as before, the increase in area of the event horizon would be the same as before,and would not reflect the fact that the sheet carried information.
I would have to conclude that, in fact, the area of the horizon does
not say anything about the information that went into a black hole and
that as far as black holes are concerned, entropy and information are
not linked.

Is this sound logic?
 
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  • #2
kurious said:
Is this sound logic?
No. The "information" talked about with entropy isn't writing on a piece of paper, its much more fundamental: atomic/molecular structure type info.
 
  • #3
basically the information that can be found is the atomic bonds before it was belived that once somthing went into a black hole it became the black hole and all bonds were broken in fact there are still bonds between the atoms in a black hole and that's the type of information they are talking about
 
  • #4
RUSS WATERS:

No. The "information" talked about with entropy isn't writing on a piece of paper, its much more fundamental: atomic/molecular structure type info.

Kurious:

How does the area of the event horizon relate to this atomic/ molecular structure info?
I think Beckstein said that one unit of area = one bit of information.
I could cut the heavier sheet of paper so that it had the same number of bits as
the lighter sheet.But how would the absorption of the sheets be distinguished by the area of the event horizon of a black hole?
 
  • #5
kurious said:
Kurious:

How does the area of the event horizon relate to this atomic/ molecular structure info?

It doesn't; apparently, it is generally accepted that no info can be obtained outside the event horizon except 3 quantities: mass, angular momentum and charge.

I think Beckstein said that one unit of area = one bit of information.

Kurious; you ask the darndest questions! :smile:
What Bekenstein said was that the entropy S of a black hole is a universal multiple of its surface area, A.
The formula:
S ={kc*3/4Gh}(A)
...(where the first bracket {} contains the usual constants.)

As a BH radiates into space it will gradually evaporate; Since its surface area A decreases so also will its entropy decrease.

Creator
 
  • #6
But how would the absorption of the sheets be distinguished by the area of the event horizon of a black hole?
 
  • #7
kurious said:
But how would the absorption of the sheets be distinguished by the area of the event horizon of a black hole?

Be distinguished? Don't know what you are referring to.
Apparently anything thrown into the BH increases its surface area (of the event horizon) and thus its entropy.
 

FAQ: Entropy & Black Holes: The Relationship Between Area & Information

What is entropy and how does it relate to black holes?

Entropy is a measure of the disorder or randomness in a system. In the context of black holes, entropy is related to the number of possible microstates (or configurations) of particles within the black hole. This is because black holes have a strong gravitational pull that prevents anything from escaping, causing the particles to become highly disordered, leading to a high entropy state.

How is entropy connected to the area of a black hole's event horizon?

The area of a black hole's event horizon is proportional to its entropy. This is known as the Bekenstein-Hawking formula, which states that the entropy of a black hole is equal to one-quarter of its event horizon area divided by the Planck length squared. This relationship suggests that the information contained within a black hole is encoded on its event horizon's surface area.

What is the relationship between entropy and information?

Entropy and information are closely related concepts, with entropy representing the amount of uncertainty or randomness in a system, and information representing the amount of knowledge or organization. As the entropy of a black hole increases, the information contained within it also increases, suggesting that black holes have a maximum capacity for information storage.

How does the concept of entropy help us understand black holes?

The concept of entropy helps us understand black holes by providing a way to measure their properties and behavior. By studying the relationship between entropy and the area of a black hole's event horizon, we can gain insights into the fundamental nature of black holes and their role in the universe.

Can entropy be reversed in the context of black holes?

In classical physics, entropy can never be reversed, meaning that a system will always tend towards higher entropy. However, in quantum mechanics, there is a theoretical concept known as the "black hole information paradox" which suggests that information may not be lost in a black hole, and that it may be possible to reverse entropy in this context. This is an area of ongoing research and remains a topic of debate among scientists.

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