Thread

1. haitchfivee · 1790354524 · focus · HN ↗

   My nitpick is with something the author said in passing about Hawking. Yes, around 1970 Hawking and the scientific community at large still used to believe nothing could escape a black hole, and between 1971 and 1973 Hawking along with Penrose and others expanded their evolving understanding and consequences of of Albert Einstein's breakthrough work.

   But then Hawking argued back the opposite case, which in simple terms means that some things can, indeed, escape an event horizon. In fact, name dropping Hawking just to mention his views as they stood before his 1973 work, and his 1974 model of Hawking radiation seems dangerously incomplete journalistic reporting.

   In 1974 Hawking formulated what we now know as Hawking Radiation, which is the *exact opposite* of what was previously believed about the impossibility of anything coming back from a black hole. Whilst still not conclusively proven as a physical fact, this did win him the Special Fundamental Physics Prize in 2013. specifically for his discovery of Hawking radiation from black holes and his deep contributions to quantum gravity and quantum aspects of the early universe.

   1. Maxatar · 1790356614 · focus · HN ↗

      Not sure I follow your comment exactly, perhaps I am misunderstanding it but Hawking radiation doesn't involve anything escaping a black hole.

      The radiation never originates from within the event horizon. Furthermore the radiation itself does not encode any information about what fell into the black hole apart from the electric charge, angular momentum, and mass (all of which must remain conserved).

      1. arcticfox · 1790357896 · focus · HN ↗

         I don't know the slightest about this but... That list looks like it is supposed to be limited but that sounds like infinitely more information than zero?

         1. palmotea · 1790362112 · focus · HN ↗

            >> Not sure I follow your comment exactly, perhaps I am misunderstanding it but Hawking radiation doesn't involve anything escaping a black hole.

            >> The radiation never originates from within the event horizon. Furthermore the radiation itself does not encode any information about what fell into the black hole apart from the electric charge, angular momentum, and mass (all of which must remain conserved).

            > I don't know the slightest about this but... That list looks like it is supposed to be limited but that sounds like infinitely more information than zero?

            I don't know about electric charge, but can't you observe mass and angular momentum of a black hole from outside? I think the "no information" thing means the Hawking radiation won't let you tell you if the black hole was made from a dead star or just a really big pile of meat or what's going on inside of it.

            IIRC, all Hawking radiation does is provide a mechanism for a black hole to eventually decay.

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