Do Black Holes Actually Possess Entropy?

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Black holes are characterized by their inability to allow anything to escape once crossed the event horizon, making their interiors unknowable. The entropy of a black hole is proportional to its area, with only three parameters—area, charge, and spin—needed to describe them. Despite the difficulty in understanding the microstates within a black hole, it is argued that their entropy is high due to their capacity to absorb mass and energy. The entropy balance suggests that as mass and radiation enter a black hole, the system's entropy increases continuously. This indicates that black holes possess significant entropy, challenging the notion that their entropy could be low.
brcooke
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Hi, I'm not a physicist so the answer to this question may be elementary but I can't figure it out for myself:

Black holes are famous because (almost) nothing can escape from them. Once an observer has crossed the event horizon, no more contact may be made with him or her. Thus it will forever be impossible to know what the interior of a black hole is like, because observers that go inside will never be able to communicate with us.

Everyone knows that the entropy of a black hole is proportional to its area, and that there are only 3 parameters necessary to describe a black hole: its area, charge, and spin (right?). All of the books I've read about the subject say that astronomical-scale black holes have very high entropy (the exception being very small black holes created in the lab).

Now, my understanding of entropy is that it is proportional to the logarithm of the number of microstates that could underlie a single macrostate. My question is: Since it is impossible to know anything about the interior of a black hole, and thus anything about the microstates within it, how can black holes have entropy at all? And contrary to the popular assumption that the entropy of black holes is very large, given how easy it is to define a black hole, shouldn't that indicate that their entropy is in fact very low?

Thanks for your help!

Brad.
 
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No, I haven't, but I'm deep into the holographic principle as suggested. I will check that next. Thanks!
 
I think that entropy of black hole is very high due to its capability of absorbing everything. Talking at macroscopic level, if we consider black hole as a system, then mass as well as heat in form of radiations are going into the system and not coming outside.
So, if we use the relation of entropy balance:
S in - S out + S gen = dS sys
S out=0 and S gen is positive
Thus Change in entropy of system(R.H.S) is positive.
Therefore we can say that the entropy of black holes is increasing continuously at a high rate meaning that it has very high entropy
 

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