Can a small black hole exist inside a larger black hole?

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Discussion Overview

The discussion revolves around the possibility of a small black hole existing within a larger black hole, exploring implications for their properties and interactions. Participants consider theoretical frameworks, potential observational consequences, and the nature of black hole dynamics.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants propose that a mini black hole could exist inside a larger black hole, raising questions about the evolution of its microstates and whether it could disappear without being observed from outside.
  • One participant mentions that general relativity allows for black holes to collide and merge, suggesting that a small black hole could fall into a larger one, potentially unnoticed due to time dilation effects.
  • Another participant refers to a moderator's claim that the Schwarzschild metric is a unique solution for black holes, questioning the meaningfulness of a small black hole existing within a larger one.
  • Some participants express skepticism about the static nature of the Schwarzschild solution, suggesting that dynamic interactions, such as collisions, could allow for a small black hole to exist temporarily within a larger black hole's horizon.
  • There is a request for further resources or links to clarify the mathematical implications of having a small black hole inside a larger one.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility and implications of a small black hole existing within a larger black hole. There is no consensus on the validity of the Schwarzschild metric in this context or the nature of black hole interactions.

Contextual Notes

Participants acknowledge the limitations of their understanding and the need for further mathematical clarification regarding the existence of a small black hole inside a larger black hole.

kurious
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Can a mini black hole exist as a black hole, inside a black hole of a few solar masses? If so,would this mean that we would not only be ignorant of the evolution of the microstates of the mini black hole as time passes - we would also be ignorant of the evolution of the total mass, angular momentum and charge of the mini black hole - can a mini black hole disappear without trace
from observers outside a large black hole?
 
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kurious said:
Can a mini black hole exist as a black hole, inside a black hole of a few solar masses? If so,would this mean that we would not only be ignorant of the evolution of the microstates of the mini black hole as time passes - we would also be ignorant of the evolution of the total mass, angular momentum and charge of the mini black hole - can a mini black hole disappear without trace
from observers outside a large black hole?

a partial answer:
the ordinary GR theory in which black holes were first predicted
allows black holes to collide and merge

and people do numerical GR simulations of that kind of thing on computers
on the web you can see comic strip sequences of computergenerated pictgures of black holes colliding

I don't see any reason a little BH couldn't fall into a big one, and because of timedilation troubles we on the outside might not actually be able to see it fall thru the horizon

but in "reality" whatever that means the little black hole would exist inside the big one and, I guess, be succcckkkked into the center of the big one and slurped. And I guess the computer people could easily simulate that and crank out pictures of it happening.

essentially the little black hole would be falling in just the way a lot of other stuff is falling in----stones, old copies of Time magazine, cast-off Television sets, and whatever else.
 
One of the moderators on sci.physics.research says that a small black hole in a big one is not meaningful because the schwarzschild metric is a unique and spherically symmetric solution for a black hole - do you agree with this?
 
kurious said:
One of the moderators on sci.physics.research says that a small black hole in a big one is not meaningful because the schwarzschild metric is a unique and spherically symmetric solution for a black hole - do you agree with this?

well I defer to any experts, but the schw metric is a static solution that describes a black hole that looks exactly that way forever

I don't imagine one could have a static situation with a little BH inside the horizon of a big BH

But I can imagine a dynamic situation in which BHs collide and merge (producing a wonderful brief storm of gravity waves as they do)

and I can picture a little BH falling towards a big one----on its way to eventual destruction----and their horizons merging amoeba-style as the little one is eaten----and it seems to me that at least temporarily there should be two singularities inside the large one's horizon

it this is impossible mathematically then there's a clearcut issue to discuss here and obviously my intuitive picture is wrong, but I need a good link to something on the web to show me that---do you have the SPR Cornell archive link to that?
 

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