Singularity or just a very small, massive shell?

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    Shell Singularity
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Discussion Overview

The discussion centers around the nature of black holes, specifically whether matter falling into a black hole reaches the singularity or forms a massive shell around it. Participants explore concepts related to gravity, relativistic mass, time dilation, and the behavior of objects near black holes, touching on both theoretical and conceptual aspects.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants propose that as objects approach a black hole, they would slow down and become more massive, suggesting they might never reach the center but instead form a shell around it.
  • Others challenge the idea of objects slowing down as they accelerate, questioning the basis for this claim and discussing the implications of time dilation.
  • One participant introduces a thought experiment involving a spaceship traveling at near-light speed, arguing that if time dilation worked as suggested, interstellar travel within a human lifetime would be impossible.
  • Another participant asserts that if an object is not dense enough to form a black hole in its own reference frame, it cannot be considered a black hole in any frame, challenging the relativistic mass increase argument.
  • There is a discussion about whether matter falling into a black hole will ever reach the center, with some suggesting that it will due to gravitational attraction, while others remain uncertain.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the behavior of matter near black holes and the implications of relativistic effects. The discussion remains unresolved, with no consensus reached on whether matter actually reaches the singularity or forms a shell.

Contextual Notes

Some limitations include the dependence on definitions of black holes and relativistic mass, as well as unresolved mathematical steps related to time dilation and gravitational effects.

  • #31
The easy way out is to say that a singularity has a finite mass and an infinite density.

However we don't have a good mathematical description of a singularity, so we don't really know.
 
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  • #32
em370 said:
Are singularities actually finitely dense? The basis of the singularity is that gravity is so strong that the object contracts without stopping and will never slow down as their is nothing to stop it( I could be wrong in this as shown by my previous immense lack of understanding). Will it really become infinitely dense or do we just say that because it will continue getting denser and denser to the point where it would no longer make any sense or even matter to measure the density? I read something on the internet about the Schwarzschild radius but I think it was talking about the size of the event horizon instead of the actual singularity.

Vorde said:
The easy way out is to say that a singularity has a finite mass and an infinite density.

However we don't have a good mathematical description of a singularity, so we don't really know.

I refer you both to this thread https://www.physicsforums.com/showthread.php?t=226671
 

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