Subject: black hole microstates
https://phys.org/news/2024-05-...

"The Bekenstein-Hawking entropy formula, which describes the thermodynamics of black holes, was discovered in the 1970s," Vijay Balasubramanian, co-author of the paper, told Phys.org. "This formula suggests that black holes have an entropy proportional to the area of their horizons.

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The recent work by Balasubramanian and his colleagues introduces a new way of thinking about black hole microstates. Their model specifically describes them as quantum superpositions of simple objects that are well-described by classical physical theories of matter and spacetime geometry.