The main issue with black holes is that you can't feed them too much stuff at once unless it falls directly into them, which won't happen in a galactic environment since everything has orbital momentum.

Once a black hole has an accretion disk, the disk itself has so much energy that it will shove away extra matter trying to fall into it.

Thus, one theory on the formation of supermassive black holes is the "black hole star".

Put simply, the idea is that in the early universe in areas where there weren't any particularly big things or galaxies it would be possible for light years worth of diffuse gas to begin accelerating towards the same area, which could collapse directly into a singularity.

It would still have enormous amounts of gas falling towards it, though, and the sheer gravity of all this gas could overcome the energy emitted by the relativistic accretion disk and continue to grow the black hole at a prodigious rate.

Eventually the balance would break and it would explode, but most of the remaining gas might not reach escape velocity, this would be the "seed" of a potential galaxy.

I lean towards the "seed" idea, because black hole formation and growth as we understand it requires that supermassive black holes had to form already extremely massive relative to an 'ordinary' black hole.

A sufficiently energetic collapse to cause a supermassive black hole straight out is extremely unlikely to occur if things are already in any kind of orbit.

We still don't really know, but it's pretty interesting nonetheless.

>There’s absolutely nothing that could make it actually stop.

Nah the Earth's core could theoretically be stopped.

Just throw several moons/planetoids at it. The first one or two to blast the surface out of the way, the next to counteract most of the angular momentum, and maybe another one to really fine-tune things.

Interestingly enough, I remember reading a study awhile back that some people (with ADHD, I think?) are less likely to be motivated to do a thing if they talk about it a lot.

IIRC, the conclusion was that some peoples' brains can decide that doing a thing and talking about doing a thing are 'close enough'.

It's theoretically possible to convert somebody into light and they would then travel at the speed of light, but I have no idea how they might rematerialize at their destination.

The placebo effect has been proven to be, ironically, quite powerful, in several cases.