What Is the Estimated Entropy of the Final Crunch in a Closed Universe?

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The discussion centers on Roger Penrose's estimation of the entropy of the final crunch in a closed universe, referencing the Bekenstein-Hawking Formula. Penrose suggests that the entropy per baryon would be 10 to the 43rd power, leading to a total entropy for the big crunch of 10 to the 123rd power. The use of a black hole analogy serves to provide a crude estimate of this entropy, emphasizing the theoretical nature of the calculation.

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Roger Penrose said:
we are considering a closed universe so eventually it should recollapse, and to estimate the entropy of the final cruch by using the Bekenstein-Hawking Formula as though the whole universe had formed, would give an entropy per baryon of 10 to the 43rd power, and the ‘absolutely stupendous total’ for the enture big crunch being 10 to the 123rd power.
what he meant by that ?
thank you.
 
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He said, "as though." He's just using a black hole as an analogy to make a very crude estimate for the total entropy.
 
Bill_K said:
He said, "as though." He's just using a black hole as an analogy to make a very crude estimate for the total entropy.
thank you Bill_K for the clarification.
 

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