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9405460 No.9405460 [Reply] [Original]

How do you guys feel about powering near light-speed spacecraft using blackholes?

Sounds stupid, I know, however given that our understanding of how black holes work is correct we could create a blackhole (say, via a kugelblitz made using energy generated by a dyson sphere) we could throw an asteroid into it and use the energy generated by the hawking radiation, which is basically pure energy, which we could use for accelerate to near light-speed.

Does this sound reasonable, or is it meme-tier pop science?

>> No.9405462

youd need a massive amount of energy to get usable radiation, like a star. why not just use the star as energy to start with. its self defeating.

>> No.9405482

>>9405462
In the paper I read (from memory) the main point is that once you have the blackhole it's there forever, unless you stop feeding it asteroids and shot.

I went back and read the specifications and in order to generate a blackhole which would meet the requirements stated in the article all you'd need is

"A high-efficiency square solar panel
a few hundred km on each side, in a circular orbit about the sun at a distance of
1,000,000 km, would absorb enough energy in a year to produce one such BH"

For those interested, the paper itself is here: https://arxiv.org/pdf/0908.1803v1.pdf
I haven't been bothered to go back and reread the whole paper, yet.

>> No.9405496

>>9405460
>say, via a kugelblitz made using energy generated by a dyson sphere
Why would you make ball lightning with a Dyson sphere?

>> No.9405504

>>9405460
The real problem with using black holes as an energy source is that moving it along with your spaceship would be extremely difficult because by default black holes don't really interact electromagnetically.

>> No.9405508

>>9405460
How do you propose we feed this micro black hole matter? "Throwing an asteroid into it" is not a valid solution. The size of its event horizon would be subatomic, you'd have a hard time feeding it even with precise particle beams or lasers.

>> No.9405510

>>9405460
>Does this sound reasonable, or is it meme-tier pop science?
It's not even meme tier. You obviously don't know what hawking radiation is if you think it's a viable power source, and any travel method that requires a dyson sphere is by default idiotic (protip: you need ftl to build a dyson sphere in the first place)

>> No.9405513

>>9405460

We have to know if blackholes are even a thing (for certain) before we can start using them.

If you're thinking purely theoretically then, hey, sounds cool. How close to the event horizon would we have to be to collect that energy though? And how would we?

>> No.9405518

>>9405510
You wouldn't technically need ftl to build a dyson sphere if you had enough material in your own solar system, a civilization could theoretically take a super long time to do it. It would also depend on the size of the sphere. And a whole ton of other things, wouldn't it?

>> No.9405532

>>9405460
You'd need a VERY VERY VERY small black hole to;
1. have it emit significant quantities of Hawking radiation
2. be able to carry it around with you.

It's really no more than a reasonably (more so than fission or fusion, less so than anti-matter) efficient means of converting mass into radiation. Besides which, the hole would be sub-microscopic and you couldn't feed it fast enough. It would continue to shrink and eventually blow up in your face.

If we had the technology to do what you suggest, there are better, cheaper, and safer ways of building starships.

>>9405504
Black holes can maintain a charge and be moved around that way. Unfortunately, they quickly suck in opposite charges; you lose your "handle", and are then in the soup as the hole eats YOU.

>> No.9405543

>>9405518
A Dyson field is more reasonable.

>> No.9405742
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9405742

Broke: using black holes to move yourself through the universe at a fraction of lightspeed
Woke: using Alcubierre drives to move the universe around you at faster-than-light speeds

>> No.9405749

>>9405742
Broke: using black holes to move yourself through the universe at a fraction of lightspeed
Woke: using Alcubierre drives to move the universe around you at faster-than-light speeds
Joke: Taking a left turn at Albuquerque

>> No.9405905
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9405905

what part about black holes makes you think you can pull energy out of them.

>> No.9406252
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9406252

>>9405742
Broke: Not having an understanding of modern physics and being too retarded to realize that we'll never break lightspeed.
Woke: Finding a way to colonize the galaxy through sub-relativistic Von Neumann probes. Achieving immortality by uploading the mind to the network or advanced biological manipulation. Creating god-like artificial intelligence and melding with it to elevate humanity to godhood.
Joke: (you)

>> No.9406371

>>9406252
Woke: https://www.youtube.com/watch?v=L9IWQwIJZHo

>> No.9406903

>>9405460
What WOULD work is having two black holes (or neutron stars or even white dwarfs) closely orbiting each other.
A ship could fall into the system and be flung away at a good fraction of lightspeed. Quite safe so long as you didn't get TOO close and didn't interact too much with the magnetic fields of the bodies.

Building such a gravitational catapult is left as an exercise for the student.