Why is it so accepted that matter falls into black holes?

[Astroboy123]

couldn't the dip made by a black hole create a lensing effect that locks light into an "orbit" around the hole past the EH?

This is a cool idea. Also, wouldn't light that is close but not beyond the event horizon experience strong lensing as well? There are cases when astronomers see duplicate images of galaxies due to strong gravitational lensing so it seems like a black hole would create a significant observational distortion. Maybe some of the objects we see swirling around black holes are figments of distortion.

 

[tkav1980]

I am probably totally wrong here but...

Imagine you just made your bed. You reach down at the exact center of the sheet and ball it up in your fist. When you do that the part of the sheet outside of your fist gets wrinkles and waves. All of the wrinkles and waves have troughs that start at your fist and extend out away from it. Now flip that picture upside down and imagine that sheet is very rigid. Pick any wave and put a bb in it. It can't climb the wave and get out because it doesn't have enough energy. It can only roll down toward your fist. The steeper the slope from flat sheet to your fist, the more energy it would take for the bb to roll up and out. Gravity kind of works like that, The bigger an object is the deeper the "dent" it makes in space. Esentially a steeper slope that you have to fight to get away from it.


Now with a black hole, it hase the deep dent of at least the mass of a large star, but all that weight on the sheet is focused at a single point. Imagine you made a dent in a sheet with a BB that weighed as much as a bowling ball.

Thats the way i visualize it in my head since its a 2D sheet bending into a 3rd dimension. I assume, again just guessing, that the distortion of space is exponentially more complex than that simple picture.


Now for light not getting out because its velocity isn't great enough I take that picture of a heavy BB in the center of a crumbled sheet and twist the sheet around. That takes all those paths and twists them up. Then I imagine that its twisted so much that no matter how hard you roll a lighter bb it either can't get up the twisted ramp at all or when it gets to the end of its twisted ramp and almost out it ends up at the mouth of the next ramp which directs it back down toward out heavier BB.

I'm not educated in the field but after a lot of reading and seeing different graphics on black holes and large bodies in space this picture makes sense to me when I am reading and tying to imagine what's going on. A friend of mine who is a graduate student in physics said the best way he could explain it to me so I could actually understand it was that the geometery of space time inside the EH was such that light can't find a path out. The space is warped in a way that it kind of curls back into itself. So if a photon thinks its going straight and heading for the EH its actually following a curved path that will never reach the EH.


Keep in mind he was trying to convey in words something he said is really better defined mathematically, and to top it off explaining it to someone who really won't actually understand it without understanding the math.

Hope that helps and if it doesn't I'd love for someone to tell me where I am going wrong.

 

[DaveC426913]

I am probably totally wrong here but...

Imagine you just made your bed. You reach down at the exact center of the sheet and ball it up in your fist. When you do that the part of the sheet outside of your fist gets wrinkles and waves. All of the wrinkles and waves have troughs that start at your fist and extend out away from it. Now flip that picture upside down and imagine that sheet is very rigid. Pick any wave and put a bb in it. It can't climb the wave and get out because it doesn't have enough energy. It can only roll down toward your fist. The steeper the slope from flat sheet to your fist, the more energy it would take for the bb to roll up and out. Gravity kind of works like that, The bigger an object is the deeper the "dent" it makes in space. Esentially a steeper slope that you have to fight to get away from it. Now with a black hole, it hase the deep dent of at least the mass of a large star, but all that weight on the sheet is focused at a single point. Imagine you made a dent in a sheet with a BB that weighed as much as a bowling ball.

Thats the way i visualize it in my head since its a 2D sheet bending into a 3rd dimension. I assume, again just guessing, that the distortion of space is exponentially more complex than that simple picture. Now for light not getting out because its velocity isn't great enough I take that picture of a heavy BB in the center of a crumbled sheet and twist the sheet around. That takes all those paths and twists them up. Then I imagine that its twisted so much that no matter how hard you roll a lighter bb it either can't get up the twisted ramp at all or when it gets to the end of its twisted ramp and almost out it ends up at the mouth of the next ramp which directs it back down toward out heavier BB.

I'm not educated in the field but after a lot of reading and seeing different graphics on black holes and large bodies in space this picture makes sense to me when I am reading and tying to imagine what's going on. A friend of mine who is a graduate student in physics said the best way he could explain it to me so I could actually understand it was that the geometery of space time inside the EH was such that light can't find a path out. The space is warped in a way that it kind of curls back into itself. So if a photon thinks its going straight and heading for the EH its actually following a curved path that will never reach the EH. Keep in mind he was trying to convey in words something he said is really better defined mathematically, and to top it off explaining it to someone who really won't actually understand it without understanding the math.

Hope that helps and if it doesn't I'd love for someone to tell me where I am going wrong.

Remove the part about all the folds and waves. The funnel is a perfectly smooth curve, thus:
[URL]http://www.timeenoughforlove.org/images/blackhole6.jpg[/URL]Also, it's not that light can't "find" a way out, it's that all paths (which are smooth curves) lead back into the BH, rather than outward.

(One path passes outside the EH, the path crosses the EH, and as such will never cross it again.) (EH not shown).
[URL]http://www.strings.ph.qmul.ac.uk/~bigdraw/penrose/funnel-main.jpg[/URL]

 

[Drakkith]

I just wanted to point out that Daves picture is just a 2d visual representation of the concept. In reality spacetime is not curved "down" or "up" and massive objects don't make dents in 2d sheets. Or trampolines. So don't imagine a large object above that funnel.