Eli5: How do Black Holes work?


I have a very big interest in them, but to be honest they beat my logic. Can’t say I don’t know anything about them, but for certain I could use some help to understand them. Especially the fact why everything around them is distorted.

In: 0

2 Answers

Anonymous 0 Comments

Matter bends spacetime towards itself, and that bent spacetime redirects things existing in or traveling through that part of spacetime towards the center of mass of whatever the chunk of matter is. The more matter you have, the stronger the bending of spacetime.

Black holes are extreme areas of bent spacetime. At the center of a black hole is a singularity (we think), which is a point of infinite density (we think) and extremely high mass. The singularity bends spacetime so much that it creates an area around itself that is impossible to escape, entirely because you’d have to travel faster than the speed of light. The edge of this area is the event horizon, and because nothing can pass through the event horizon moving away from the black hole, nothing that passes through it can be seen, hence why black holes are black.

In addition, the extreme gravity doesn’t just end at the event horizon, but extends outward from the black hole the same as any gravitational field produced by any other kind of matter. Thus, you get gravitational lensing, where light is actually bent around the black hole by the extreme gravity, which typically manifests as stars appearing to move out of their normal position from an observer on the other side of the black hole. Note that this isn’t unique to black holes, but also happens around all stars (and all bits of matter, although the effect gets too small to notice when you get to smaller stars), including our own; you just normally can’t observe light being bent around the star because it’s too bright to take an observational reading. This actually ties in to how relativity was proven in the first place; scientists took measurements of the stars near the Sun during a solar eclipse, and found that they all appeared to have moved out of position away from the Sun.

Anonymous 0 Comments

The royal institute has a video on youtube called ‘whats inside a blackhole’ or something similar. It was a super good watch imo.

Blackhole stuff isnt well known and lots of things are just theorized.

One takeaway was that with a large enough black hole something may be able to survive entering one (not being turned into sphagetti). It also talks about the idea that blackholes may lead into (and be) other universe (like a multiverse).

We think there was a big bang that everything is moving away from which is sort of the inverse of a blackhole (with everything flowing in).

Cool stuff to think about anyways!

*i didnt really answer your question but that video does