Comment on "Black Hole Entropy: A Closer Look"
Related Experiment Video
Updated: Nov 27, 2025
Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
Pedro Pessoa1, Bruno Arderucio Costa2
1Department of Physics, University at Albany (SUNY), Albany, NY 12222, USA.
Abstract:
In a recent paper (Entropy 2020, 22(1), 17), Tsallis states that entropy-as in Shannon or Kullback-Leiber's definitions-is inadequate to interpret black hole entropy and suggests that a new non-additive functional should take the role of entropy. Here we counterargue by explaining the important distinction between the properties of extensivity and additivity; the latter is fundamental for entropy, while the former is a property of particular thermodynamical systems that is not expected for black holes. We also point out other debatable statements in his analysis of black hole entropy.
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