I would like to know why is it when i try to remove this white looking string from the inside of my belly button a black hole appears?

2 answers: Professional answer: Lint can build up in the belly button and when removed can reveal the confluence of tissue surrounding where the umbilical cord was cut which can look like a hole in those with inverted belly buttons. Unprofessional answer: You have discovered an alternative universe in your belly button where string theory and black holes have a modifiable existence influenced by you.