Entropy & Black Holes: The Relationship Between Area & Information

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Discussion Overview

The discussion centers on the relationship between entropy, information, and the area of the event horizon in black holes. Participants explore theoretical implications regarding how information is treated when objects, such as sheets of paper, fall into black holes, and whether the area of the event horizon reflects the information contained in those objects.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant argues that the area of the event horizon does not reflect the information contained in objects falling into a black hole, suggesting that entropy and information are not linked in this context.
  • Another participant counters that the "information" related to entropy is more fundamental, referring to atomic and molecular structure rather than written information.
  • Some participants discuss the idea that atomic bonds may still exist within a black hole, challenging the notion that all information is lost upon entry.
  • There is mention of Bekenstein's principle that relates the entropy of a black hole to its surface area, with one unit of area equating to one bit of information.
  • Questions arise regarding how the absorption of different sheets of paper would be distinguished by the event horizon's area, indicating uncertainty about the implications of this relationship.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between entropy, information, and the event horizon. There is no consensus on whether the area of the event horizon can convey information about the objects that fall into a black hole.

Contextual Notes

Participants highlight limitations in understanding how information is preserved or lost in black holes, particularly regarding the nature of the information and its relation to the event horizon's area. The discussion reflects a dependence on theoretical concepts that may not be universally accepted.

kurious
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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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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.
 
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
 
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?
 
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
 
But how would the absorption of the sheets be distinguished by the area of the event horizon of a black hole?
 
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.
 

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