I need an explanation of gravity's effects.....sorta hard to grasp, maybe... but help?.?

Question

I'm studying... gravity and how it works around a sun or around a black hole...

when we see the diagrams of a black hole with Hawking radiation, perhaps...they are all shown as the black part, surrounded by an 'event horizon'...in a FLAT PLANE..... this doesn't make sense to me.....

same deal with the illustrations of the 'fabric' of space that is affected by the mass of an object like the Sun... it shows a deep 'well'..... nice, but still doesn't make sense to me....why?...

because, if an object like a black hole or a Sun is affecting space around it gravitationally, then it should be happening in ALL PLANES, not just the one, yes?.....

so an 'event horizon' would be round like a huge star?.... with the jets of Hawking radiation shooting out of WHERE?... there would be no 'poles' on the singularity unless it was rotating, yes?.....and if it IS rotating, then the jets coming out of black holes would be straight lines.... but we are shown illustrations of them sometimes

Answer 1

Its because it cant be drawn or illustrated, you can only imagine what it should look like, when you look at the sun you see a yellow disc,in 6 months time we are at the other side of it but you still see a yellow disc, if you could go to the top of it you would still see a yellow disc, the same with the bottom.Its the same with a black hole, no matter which way you observe it from it would still look the same.

Answer 2

Gravity is fully 3-dimensional, and I think you're on the right track, but just getting thrown off a bit by the 2-D illustrations.  The "gravity well" image is a great 2-D analogy for what's happening in 3 dimensions, you just have to realize it's only an analogy.  Matter warps spacetime around it.  The closer you get, the more spacetime is warped.  That's all the image is trying to illustrate.

The singularity is at the center of the black hole, it is the place where most of the matter that has been sucked in is compressed into a single point by newer matter.  The event horizon is a sort of "sphere" around the black hole, it is the distance from the center where light can no longer escape.  Black holes do spin and they do have poles but the matter inside is mostly in a spherical shape.

Hawking radiation is as of now undetectable and probably doesn't exist (it has never been proven).  If it does exist, it may or may not escape in jets.  However, many black holes DO have jets (of matter).  Because they are spinning, matter that is falling into the black hole is orbiting very fast and coalesces into a disk around the black hole, kind of like how all the planets orbit the sun in a flat plane.  As the matter falls into the black hole, a lot of it gets caught in the intense magnetic fields surrounding the black hole and spirals up toward its poles.  That is why sometimes you'll see a picture of a black hole and it has a disk around it with jets on the top and bottom.

Answer 3

Yes, the event horizon is a sphere around the black hole. The accretion disks tend to form around rotating black holes (and most *are* rotating), so that's what the artists draw. But yes, the fabric of spacetime (not just space) is affected in a spherically symmetric way. In essence, what the artists renditions give is a cross section view, not the whole view.