Are singularities shaped as a sphere.

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    Singularities Sphere
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Discussion Overview

The discussion revolves around the shape of singularities in black holes, particularly whether they are spherical or take on other forms. Participants explore theoretical aspects of black holes, including their event horizons and the nature of singularities, while addressing both rotating and non-rotating black holes.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants suggest that for non-rotating black holes, the singularity is a point with no dimensions, while rotating black holes may have a ring-shaped singularity.
  • It is noted that the event horizon of a non-spinning black hole is spherical, leading to speculation that the singularity might also be spherical, though this remains uncertain.
  • One participant emphasizes that inside the event horizon, current mathematical models break down, and the term "singularity" reflects a lack of understanding rather than a definitive description.
  • Another participant mentions that black holes are defined by their event horizons, which are roughly spherical, but acknowledges that models fail to accurately describe conditions inside the black hole.
  • A participant introduces a conceptual analogy suggesting that the universe itself might be likened to a black hole, where communication with other universes is impossible.
  • A later reply raises a question about the visibility of a spinning black hole when viewed off-set from its plane of motion, considering its zero thickness.

Areas of Agreement / Disagreement

Participants express various viewpoints on the shape and nature of singularities, with no consensus reached. There are competing ideas regarding the dimensionality and characteristics of singularities in both rotating and non-rotating black holes.

Contextual Notes

Participants acknowledge limitations in current models and the understanding of singularities, particularly regarding the breakdown of mathematical descriptions inside event horizons.

MartinJH
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I haven't read much on black holes as its not something that interests me compared to other goings on. When ever I do read/hear about them I have always pictured them as being a flat, circular plane. From what I have read they form from collaspsing stars, I understand that much. So do they remain a sphere once they get to the point in which we define them as a singularity.
 
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For a non rotating black hole the singularity will be a point, basically it is an entity which has a location in space but has no dimensions of length, area or volume.

In spinning black holes the singularity can take on a ring shape in line with the plane of motion. The ring singularity is of zero thickness, ie. perpendicular to the plane of motion, but it does have a non zero radius.
 
also a black hole has an event horizon that for a non-spinning variety is a sphere. its the surface boundary where once passed light can no longer escape from the BH.

An observer outside the BH watching objects fall into the BH will see the things hover at the event horizon and never fall in whereas the falling object will observe itself continuing to fall past the event horizon and at that point no longer able to send back any signal to the observer because the radio or light signal can't escape from the BH.
 
MartinJH said:
I haven't read much on black holes as its not something that interests me compared to other goings on. When ever I do read/hear about them I have always pictured them as being a flat, circular plane. From what I have read they form from collaspsing stars, I understand that much. So do they remain a sphere once they get to the point in which we define them as a singularity.

Inside the event horizon of a black hole, we really don't know WHAT is going it. The math models break down and so we call it a "singularity" but that's just a name for "no idea". It certainly seems that since the event horizon is spherical, then whatever is inside it is spherical but that's still a guess. Calling the singularity a dimensionless (but massive) point is a tautology --- both really just mean that we don't know.
 
MartinJH said:
I haven't read much on black holes as its not something that interests me compared to other goings on. When ever I do read/hear about them I have always pictured them as being a flat, circular plane. From what I have read they form from collaspsing stars, I understand that much. So do they remain a sphere once they get to the point in which we define them as a singularity.
Black holes as defined by their event horizon's are roughly spherical. Beyond them our models don't work very well and predict an infinitely dense point known as a singularity. As far as I understand this is regarded is not being the case by most scientists and we won't really know what goes on inside a black hole until we develop better models.
 
I've seen it stated (by someone reputable, as in an astrophysicist whose name I can't recall) that our universe can be thought of as a black hole in that no communication is possible with whatever universes, if any, lie beyond. If that is correct, then the answer to your question is all around you.
 
Thank you everyone, I appretiate the responces and read them a few times.

Rollcast, your answer I feel has answered my question, and, in a way I do understand. It has not so much stunned me but given me a lot to think about. I've never been the one for maths so its usually doing things Roger Penrose style, though with mind-drawings.

jedishrfu, phinds and Ryan; You have touched on possibly as much as I know about the subject in discussion and I knew exactly what was being said, thank you.

Also, Danger, your post has also hit a spot with me. Thinking about the universe as possibly a singularity. Thats very intriguing for me though I will take it as a pinch of salt.


Going back to Rollcasts answer briefly;
When talking about a spinning black hole what would anyone see when viewing the Black hole off-set from the plane of motion, if anything at all considering it has zero thickness. Would the presence of it only be felt.
 

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