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arXiv:hep-th/9303048 · Physical Review Letters

Entropy and area

Mark Srednicki

Published Aug 2, 1993• 1,857 citations
arXivHTMLPDF

Abstract

The ground-state density matrix for a massless free field is traced over the degrees of freedom residing inside an imaginary sphere; the resulting entropy is shown to be proportional to the area (and not the volume) of the sphere. Possible connections with the physics of black holes are discussed.
DOI
10.1103/physrevlett.71.666

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