So, let me get this straight right here.
According to Wikipedia:
"The KBC Void (or Local Hole) is an immense, comparatively empty region of space,...... The underdensity is proposed to be roughly spherical, approximately 2 billion light-years (600 megaparsecs, Mpc) in diameter. As with other voids, it is not completely empty but contains the Milky Way, the Local Group, and the larger part of the Laniakea Supercluster. The Milky Way is within a few hundred million light-years of the void's center."
So basically, the KBC void is basically the largest supervoid in the Observable Universe, and our Milky Way galaxy is inside this Supervoid. So basically, we live in the Universe's largest supervoid. This Supervoid isn't like other supervoid, which tend to contain only a handful of galaxies, like Bootes, but it contains the Laniakea Supercluster, the Local Group, including the Milky Way, which is just within a few hundred million light-years of its center. Basically, a "dense" supervoid that contains nearly 100,000 galaxies.
And here is the next part, this time, it is more about the question: Our universe is not really empty. No matter how much you try to bring the pressure to zero, you will never achieve a pure, perfect vacuum, because of one reason- Quantum Fluctuations.
Even in a vacuum, particles keep on appearing and disappearing out of existence. This is the same force that drives Hawking radiation (RIP Black hole), and maybe the same force that caused the Big Bang(Very theoretical). But that is not the question, we are now moving on to the actual question.
"Vacuum" Hydrogen Mines
In this story, Humans, who have already became a Type III+ civilisation, are now moving out of the galaxy, and are now using FTL warp drives, which are based on Casimir-Alcubierre Drives, and FTL communication, made by wrapping radio-wave photons in a Warped-spacetime packet, which will assist them at much higher speeds to their destination. Their empire is called the Laniakea Empire.
Now they are planning on colonizing the entire Laniakea Supercluster, and in doing so, they discover the KBC void. They have a plan to make basically free fuel from "nothing".
First of all, they get a bunch of Supermassive black holes and magnetar and scatter them throughout the supervoid. Next, the trick is to feed them something, a starter, which could be anything. Then, the next trick is to produce a strong electromagnetic current.
As the magnetars and SMBHs' accretion disks produce an immense amount of electric charges and powerful magnetic field, the result is that the strong electromagnetic fields rip away particles from the quantum vacuum, and turn them into Actual particles, like quarks and gluons, which will be further used to make protons and electrons. These protons and electrons will then be used to make hydrogen. Part of the hydrogen will go into further feeding the SMBHs and magnetars, while the rest is dispersed into the void/used in fusion reactors for power-generation/ further fused to make heavier elements like iron, silicon, carbon, oxygen etc. This essentially makes it a sort of "Hydrogen-breeder reactor", as though the "reactor" consumes matter for producing the powerful electromagnetic field, it in return produces much more matter (Hydrogen).
One of the problems is that, the reactor produces both Hydrogen and Anti-hydrogen. The big problem is that I don't want them both to contact each other and annihilate. One of the easiest ways to do this is to dump the antimatter into a black hole. However, this would be a massive waste of resources, as nearly half of the output is thrown away.
Instead, I want to convert the anti-hydrogen, into normal hydrogen. This way, I can ensure that none of the products are wasted.
How can I convert the Anti-Hydrogen into Normal hydrogen from my "Vacuum Hydrogen" reactors?
Reasons why the humans are building this:
- This takes place maybe about 20 million years in the future. Humans are now aware that hydrogen is rapidly dwindling in the observable universe, and in just a few trillion years, hydrogen is going to get polluted with heavy elements, which will render star formation almost impossible. Any star formed would be incapable of sustaining life. The civilisation strives to live much longer than just a few trillion years.
- Another reason, is to make sure that the hydrogen produced will make more stars and planets. The humans are aiming at "creating" life. The aliens will be used as labor force for their empire.
- The fusion of hydrogen to create heavier elements like iron, silicon, uranium, gold is also very important for the economy of the Laniakean Empire.