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Black Hole/singularity question?
From what I'm aware singularities can/do spin - I'm curious would this added momentum at all affect the general shape shape/field of the event horizon?
The earth is bulging at its equator due to the speed of its rotation; Im aware that there is no exact "definition/mass" that makes up/defines the boundary of an event horizon and at first though I assumed no - but is it possible/true that it the shape of it could be oblong such as the shape of the earth?
Not the shape of the singularity rather the event horizon field surrounding it
4 Answers
- suittiLv 78 years agoFavorite Answer
From the wiki page: "For a non-rotating black hole, this region [the singularity] takes the shape of a single point and for a rotating black hole, it is smeared out to form a ring singularity lying in the plane of rotation."
If the singularity is not a point, the event horizon isn't exactly a sphere either.
- RaymondLv 78 years ago
There is no such thing as a "physical" shape to a singularity.
A "singularity" is a mathematical device that has to do with the domain of an equation. In the spacetime metric, we deal with mass AS IF it were concentrated at the centre of mass. For masses in general, this is true... until you hit the surface of the object containing the mass.
In the mass contained inside a black hole, there is no such object and you can "approach" the centre of mass as much as you want, AS IF the mass was concentrated in a "singular point".
We do not know if it really is. We just design the mathematics AS IF it were.
For a rotating black hole, the singularity is represented as a circle (one dimension) instead of a point (zero dimensions). Bur remember that this is the shape of the region IN THE DOMAIN where the function grows without bounds.
We still do not know what really happens there.
- MorningfoxLv 78 years ago
Yes. Black holes have three properties.
(1) Mass
(2) Electric charge
(3) Spin
There's good reason to expect that black holes have practically zero electric charge. But obviously, black holes have mass. And it would be a very rare black hole indeed that didn't have some spin. Location and velocity (including acceleration) can be added as properties of the BH. All other properties can be derived from just those main properties.
- ?Lv 78 years ago
Just wanted to let you know that there is only a three-tenths of 1 percent "bulge" at Earth's equator. It's a 42 kilometer "bulge" out of more than 12,700 kilometers of diameter. Billiard balls are manufactured to a standard of three-tenths of 1 percent difference in measured diameters. Would you call billiard balls "oblong"? By any, except the most anal-retentive, definition, Earth is a sphere.
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