The many definitions of a black hole

  title={The many definitions of a black hole},
  author={Erik Curiel},
  journal={Nature Astronomy},
  • E. Curiel
  • Published 4 August 2018
  • Physics
  • Nature Astronomy
Although black holes are objects of central importance across many fields of physics, there is no agreed upon definition for them, a fact that does not seem to be widely recognized. Physicists in different fields conceive of and reason about them in radically different, and often conflicting, ways. All those ways, however, seem sound in the relevant contexts. After examining and comparing many of the definitions used in practice, I consider the problems that the lack of a universally accepted… 
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