I guess the destiny of any object that falling into a black hole will depend on its size and the density of the black hole it falling in. And from distant observer it should looks different.

  1. A small, very dense black hole with 1 Solar mass and object metallic meteorite: the meteorite will be destroyed by tidal forces and electrons in each atom will fall in to nucleus, forming neutrons. When this will close to the event horizon, it will from a mini black hole. This process will take very long time for distant observer.

  2. Huge 50 Billion solar mass black hole with density < water and object metallic meteorite: Because of the density of the gravitational field G and small dG/dL and mass and density of mater in meteorite event horizon for meteorite will form long before reaching black hole. Distant observer can see how the meteorite become a black hole, and its event horizon grows as it approaches the huge black hole. The meteorite will not be destroyed by tidal forces. Process for distant observer will be much faster.

Did I miss something?

  • $\begingroup$ Yes, black holes of different mass will behave differently, however, even the accretion zone of a galactic black hole is a violent region. Stars that get pulled in are being torn apart and the plasma does create x-rays, which means that there are very high temperatures and probably some low energy nuclear reactions going on. If the black hole is starving, the region may be relatively free of such effects. $\endgroup$ – CuriousOne Jul 27 '16 at 18:43
  • $\begingroup$ I tried to repair your grammar/spelling. I would suggest to take a little course about the correct usage of the articles. I can't understand and thus I can't repair your following sentence: "Because of the density of the gravitational field G and small dG/dL and mass and density of mater in meteorite event horizon for meteorite will form long before reaching black hole." I suggest to take it apart into some smaller ones. $\endgroup$ – peterh Jul 28 '16 at 0:45

The tidal forces are volume preserving, that is they distort the shape of an object but do not change its volume. This is because the Ricci tensor is everywhere zero. So an object falling into a black hole will not itself become a mini black hole at any point in its fall.

You are correct that the tidal forces are greater for smaller black holes than larger ones, so for any infalling object there will be some black hole mass below which the object is disrupted by the tidal forces.

Note that an external observer will never see the object cross the event horizon, and this is true regardless of the black hole size.

  • $\begingroup$ In practice observer can see the object cross the event horizon if event horizon will grow influenced by surrounded mass that falling in black hole or other example another merging black hole will make event horizon of both black holes grow before they merge $\endgroup$ – Din Rash Jul 28 '16 at 13:20
  • $\begingroup$ Where Ricci tensor is zero? $\endgroup$ – Din Rash Jul 28 '16 at 13:23
  • $\begingroup$ @DinRash: the analytic solutions we have for black holes are vacuum solutions. The stress-energy tensor and the Ricci tensor are everywhere zero except at the singularity where they are undefined. $\endgroup$ – John Rennie Jul 28 '16 at 14:20
  • $\begingroup$ @user104372: I have no power to reopen your question unilaterally. However I have voted to reopen. If one more person votes to reopen your question will be reopened. $\endgroup$ – John Rennie Jul 30 '16 at 13:27

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