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27. Natural Reality / E. Cosmology / 7. Black Holes

[collapsed stars emitting no light]

2 ideas
General relativity predicts black holes, as former massive stars, and as galaxy centres [New Sci.]
     Full Idea: Black holes are predicted by general relativity, and are thought to exist where massive stars once lived, as well as at the heart of every galaxy.
     From: New Scientist writers (New Scientist articles [2013], 2013.06.15)
     A reaction: Since black holes now seem to be a certainty, that is one hell of an impressive prediction.
Black holes have entropy, but general relativity says they are unstructured, and lack entropy [New Sci.]
     Full Idea: Black holes have a temperature, and hence entropy. ...But if a black hole are just an extreme scrunching of smooth space-time, it should have no substructure, and thus no entropy. This is probably the most obvious incompleteness of general relativity.
     From: New Scientist writers (New Scientist articles [2013], 2015.11.07)