I am just curious here, and I am certainly not a physicist or an astronomer, but based on the very watered down suggestions of string theory... that our entire universe is on a membrane and that all we percieve is tied to that same membrane... and that Gravity is a force that is for whatever NOT tied to this membrane, and therefore is a relatively weak force in our experience compared to other forces....
Could black holes be nothing more than what may be nothing but a relatively small amount of gravitons that have for one reason or another gotten "stuck" to the membrane, or some cascading effect that causes gravitons to become stuck, exponentially increasing their influence ?
I would assume that these possibilities have been thought of by someone far more versed and smarter than I, but I am curious.
I thought that the string theory had been discredited.
I'm familiar with the string theory conjectures to which you refer, but I can't say whether your further conjecture has merit. I don't know enough to even guess.