I do not see something spectacular in this news. Probably the gas is not as much as a torus, but more like a very slim disk. Either watched from above we see the black hole "naked" (so every kind of radiation reaches us) or we see it from the exact side of the disk (thus the radiation gets absorbed). This only partially explains it, as it very unlikely that we see almost half of the black holes from the side. Another possibility is that only the nearest parts form such a disk while the other gas is like a sphere around the center black hole (which is very likely rotating). Of course there can be anything else in between. Since the do not name their sources, it is hard to say if they left out any important information to make it more easy for the reader.
Black holes are quite simple objects (but you can write very much about them), if viewed from the outside (the inside we cannot see, so we can only assume what is going on). You can describe a black hole with only a few parameters: its mass, its electric charge and its rotation.
The normal non-rotating black hole is a perfect sphere, despite the form of any object which was the cause (Even a cubic star would create an exact spheric black hole). This only applies to the event horizon (or Schwarzschild radius), the singularity inside the black hole could be of any shape.
The rotating black hole is a spheroid, similar to earth or sun. It is a bit more complicated as the event horizon is not identical to the ergosphere created by this black hole.
The event horizon is the actual "size" of the black hole. Everything inside can never get to the outside again and will eventually be destroyed in the singularity.
The event horizon can never get smaller (except.. see below). If two black holes merge, the mass of the newly created black hole is smaller than the sum of both masses of the old black holes. The "missing" mass have become energy or gravitational waves. But the overall surface of the newly created hole (which is exactly the event horizon) is bigger than the sum of the surfaces of the merged black holes.
The Hawking radiation is a quantummechanical effect, caused by vacuum fluctations (These must exist because of the uncertainty principle by Heisenberg). If such a fluctuation is big enough and happens near enough to the event horizon, a pair of "virtual particles" can be become real ones (Usually both virtual particles annihilate after a very very short time). But if one particle gets caught by the black hole and the other moves away from it, it seems for people outside that the black hole emitted radiation.
If you look closer at this you will see, that this radiation is exactly that of a "black body". A strange effect is that the smaller a black hole is, the hotter it gets, thus radiating even more.
Btw, if you are unsure about the size: our sun would create a black hole with a Schwarzschild radius of about 3km (now the sun has a diameter of about 1.4 Million km). The earth would create a black hole with a Schwarzschild radius of 9mm.
What happens if a very small black hole of the size of an atomic nucleus would fly through the earth? Nothing probably. It would just fly through and go away.
And what happens if you would jump into a black hole? That depends on the size. If it is big enough you won't even notice that you are now inside the event horizon. If it is a smaller black hole you will get ripped to pieces long before you even reach the event horizon. The reason is the same as for ebb and flood: intertidal forces. You get streched from feet to head and get queezed perpendicularly to it. Not a fun death, i suppose.
White holes and worm holes are valid solutions of the Einstein field equations. But that does not mean they will exist in the "real world". Not every solution of a mathematical problem can be applied to the real world. You probably know this from school where you sometimes get a positive and negative solution from a calculation (Example: the Pythagorean theorem: a²+b²=c² - if you have a with 3 and b with 4 - then valid solutions for c are 5 and -5. But since there are no negative lengths, you just discard it.)
There are many more things to say, but i guess i already talked too much to give you a headache.
Re: OT: Study Reveals Flaw in Black-Hole Theory
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