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Flow Wave's tribute to LIGO: https://www.youtube.com/watch?v=qvU5ytghMdQ

That's an impressive swimming pool ;-)


So you could theoretically build a black whole generator by building a sphere that could emit gravitational waves with precision?


You'd need the sphere to be more than massive enough to collapse under its own gravity, into a black hole; such a structure wouldn't be hypothetically possible. Building black holes with anything other than stars or giant gas clouds (in the early universe) turns out to be hard; your black hole generators inevitably keep collapsing into black holes or at least neutron stars.


> You'd need the sphere to be more than massive enough to collapse under its own gravity, into a black hole; such a structure wouldn't be hypothetically possible.

I don't think that's technically true. You could build a bunch of catapults on the edge of the sphere, and when they all launch rocks at the center of the sphere, they would eventually form a black hole. The catapults could be arbitrarily far from each other as the radius of the sphere increases, such that they would not really do much to each other gravitationally. You'd just have to wait a real long time for the rocks to hit the middle.

> Building black holes with anything other than stars or giant gas clouds (in the early universe) turns out to be hard;

Well yes, galaxy-sized intelligently designed structures don't really happen.


I think by "Black hole generator" the other person meant a device which could create black holes remotely through some kind of process, not just a mass that collapses under its own gravity. In that sense, if you could find an old, spun-down neutron star (and man wouldn't that be a fun search! Massive, but tiny and dim...) then as you say, you could just keep adding mass until crush.


Any black hole generator that doesn't itself become a black hole is essentially throwing part of itself in the black hole (Yay conservation laws!). You can replace the catapults with lasers or plasma guns or whatever.


Sure, but I think the original commentator was imaging a massive sphere that could emit such powerful and precise gravitational waves, that you could create more black holes as a result. My point was just that any mass capable of achieving that, even hypothetically, would have long since collapses into a black hole.

I take your point however, that you could coordinate in some way separated masses, but at some point you'd probably run into issues with the aforementioned galactic-scale of engineering.


Some A+ structural integrity fields I suppose.


Oh yeah, with daily baryon sweeps to keep the tribbles out!


You don't need to emit gravitational waves, you can emit light that converges to a point.


This is amazing. How did you find this?


> How did you find this?

I found it extremely amazing as well! :p




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