Entropy and area.
Entropy and area.
M. Srednicki
1993 · DOI: 10.1103/physrevlett.71.666
Physical Review Letters · 1,721 Citations
TLDR
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.
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.