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If you can electromagnetically trap enough antimatter to use it as fuel you could as well trap a miniature charged black hole that can be fed regular matter to produce power, which skips the whole inefficient part of making antimatter.


Miniature black holes would just evaporate. Antimatter wouldn't.


Minor nit-pick but Hawking Radiation hasn't been observed and remains a theoretical prediction.


It's pretty widely accepted though. He himself hated the idea so you can expect he did the calculations thoroughly.


I love that major scientists had a intense hatred for the concepts forced upon them by the universe. Einstein and quantum mechanics come to mind


It's a pretty fundamental prediction though, and it's been derived in many different ways, all of which give the same prediction.

It's closely related to the Unruh effect, which is a direct consequence of pure QFT. The Unruh effect describes how an accelerated observer sees a different vacuum from an inertial observer - they see radiation that the inertial observer doesn't.

Hawking radiation is essentially this same effect, except that "acceleration" is replaced by "gravity" (Einstein's equivalence principle.) There's a bit more to it, but that's the basic intuition.

For Hawking radiation to be wrong would require some fundamental changes to GR, QFT, or both.


A lot of great science progress followed after some "fundamental prediction" turned out to be wrong :). Wouldnt it be awesome to learn that blackholes, in fact, do not evaporate at all? That would be exciting


> A lot of great science progress followed after some "fundamental prediction" turned out to be wrong

For example? What I mean by “fundamental” is that we have very strong reasons to believe in the correctness of a prediction, because e.g. it follows mathematically from more than one model (in this case), and doesn’t involve dependence on uncertain physics.

> Wouldnt it be awesome to learn that blackholes, in fact, do not evaporate at all? That would be exciting

These kinds of attitudes don’t seem to me to involve an interest in science. You don’t appear to actually have much understanding or knowledge of what we’re discussing. You’re just looking for a fix.


That's the point, evaporation turns matter into energy. You can tune power by chosing mass of the black hole and then feed it regular matter at a steady rate.


Not before efficiently converting a large amount of mass into usable energy.


In the same way that atomic weapons and radioisotope generators both convert mass into energy. It's just a matter of slightly different timescales.


But you want that to happen in space and to control the output of energy.

Otherwise you just have a bomb.


The difference between a bomb and a reactor is just clever engineering.


It's much easier to make a fission reactor than a fission bomb, and much easier to make a fusion bomb than a fusion reaction. They are not even that similar.


It's way easier to make a fission bomb than a fission reactor. I reactor has to stay in the very narrow window where it's critical but not prompt critical. Even pure fission bombs can be marvels of engineering but the simplest gun-type bomb is easier to build than the simplest nuclear reactor.


Without a precisely timed neutron initiator you'll get a fizzle. Either way, gun-type bombs require highly enriched uranium. A simple reactor can be literally just brickwork of natural uranium and graphite.

Reactors are much much simpler to pull off, which is why US had the first reactor whole 2.5 years before a nuclear bomb.


Something that explodes with the force of 100 tons of TNT is still a bomb, even if it isn't a bomb as impressive as the one you were hoping for. And getting the reactor you're thinking of to the point that it worked without exploding took a lot more effort than you're suggesting.


Introducing GoalpostMover-3000.


Dual use technology, you say?


How could we harness this energy and make it usable?


You use it to boil water.


You can even dissolve the uranium in the water and use the same substance for both fuel and propellant and so capable of reaching far higher temperatures than those that would cause any engine to melt.

https://en.wikipedia.org/wiki/Nuclear_salt-water_rocket


The real question is if we'll get back hole or antimatter powered steam engines before GTA 6


It's almost a meme at this point


If I knew that, I'd probably have more important things to do than comment it here.


You could pen a carefully-worded a letter of demands and send it to some Billionaire? A bit on the risky side, but - hey, you only live once etc.


We know how to make antimatter and have actually done it. We have no realistic way to obtain a black hole of any size.


If you can create enough AM to last a space voyage you certainly know how to build big enough particle accelerators.


This is a silly claim. Creating black holes is many orders of magnitude more difficult than creating antimatter.


Depends. Do we know how to obtain a miniature black hole?


There have been several proposals. This paper proposes a feasable mechanism[1]:

-"a SBH could be artificially created by firing a huge number of gamma rays from a spherically converging laser. The idea is to pack so much energy into such a small space that a BH will form."

1. https://arxiv.org/abs/0908.1803


The biggest problem is that if you're creating it with lasers, you're only going to get the energy out that you put in. You really want to be able to feed it matter, which would effectively make it an anything-to-gamma-radiation converter, which means you have to feed it quite a lot of matter, against the radiation pressure of all that energy coming out. The paper mentioned assumes a worst case of not being able to feed the black hole at all, but doesn't (in my skim) address the fact that this means you have to put in all the energy you'll be using for the lifetime of the black hole at the creation of it, which seems significantly more outrageously infeasible than the bare necessity of creating a black hole at all.


Does anyone address the fact that a black hole will be falling towards the center of the earth at 1g? How do you handle a black hole?


Black hole is the safest energy generator per unit of energy produced.


Use it for interstellar spacecraft, as far away from Earth as possible.


There’s a recent paper on the formation of such a “kugelblitz”; it’s argued to be unfeasible.

https://arxiv.org/abs/2405.02389


They made a movie about this. It didn’t end so well for the crew.


I admit to invoking the phrase “Where we’re going, we won’t need eyes to see” at least once a year when something feels like it’s going horribly wrong.


But it was one hell of a ride! ;-)


> a miniature charged black hole that can be fed regular matter to produce power,

What form of power and through what principle?


Hawking radiation, I think. Yes, this is at best speculatively feasible.


Probably more like a water wheel - matter spinning around the hole can be accelerated.


A spacecraft carrying a blackhole as propulsion means probably would have poor power to weight ratio.


Not at all. It would have one of the best power to weight ratios possible.

Now as to whether you could use all that power....


The romulan empire does this.




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