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Bekenstein assigns entropy to a black hole

Jacob Bekenstein published the argument that a black hole must carry entropy proportional to the area of its horizon, in order that the second law of thermodynamics survive the act of dropping a hot gas into one. The proposal was resisted, because entropy implies temperature and temperature implies radiation, and black holes were by definition objects from which nothing emerges. Shakura and Sunyaev published their accretion disc model in the same year, so 1973 supplied both the thermodynamic problem and the standard description of the material outside.

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Recorded on Black hole entropy

  1. Cygnus X-1 is localised and weighed
  2. Bekenstein assigns entropy to a black hole
  3. Hawking shows that black holes radiate
  4. Page states what unitarity requires of the radiation
  5. The Page curve is reproduced from within semiclassical gravity
  6. The first image of a black hole shadow is published
  7. The M87* ring is imaged in polarised light
  8. A second epoch shows the ring persists and the bright spot moves

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