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Can we make a black hole? And if we could, what could we do with it?

  • 142 points
  • 8 days ago

  • @nsoonhui
  • Created a post

Can we make a black hole? And if we could, what could we do with it?


@zw123456 8 days

Replying to @nsoonhui 🎙

I dunno what you could do with it but the black hole laser bit blew my mind https://arxiv.org/abs/1409.6550

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@donutshop 8 days

Replying to @nsoonhui 🎙

Would be neat to suck up all the garbage

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@mrkramer 8 days

Replying to @nsoonhui 🎙

Maybe we could make Black Hole Computers[0]?

[0] https://cse.buffalo.edu/~rapaport/111F04/lloyd-ng-sciam-04.p...

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@cletus 8 days

Replying to @nsoonhui 🎙

Black holes created from energy are called Kugelblitz black holes [1]. The article correctly points out the difficulty of doing so with traditional lasers.

But if we can ever figure out a way to reflect (and thus lase) gamma rays (or some other much higher energy radiation) this then becomes possible.

Of course we don't even have a plausible theory on how we might construct "grasers" [2].

[1]: https://en.wikipedia.org/wiki/Kugelblitz_(astrophysics)

[2]: https://en.wikipedia.org/wiki/Gamma-ray_laser

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@swayvil 8 days

Replying to @nsoonhui 🎙

If we had "reverse centrifugal force" you could create a black hole by "spinning" the thing really fast.

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@xg15 8 days

Replying to @nsoonhui 🎙

> So, if you hold the mass fixed and compress an object into a smaller and smaller radius, then the gravitational pull gets stronger.

I find this bit interesting because I'm pretty sure I've read the exact opposite before. My previous understanding was that the gravitational pull is only determined mass - but a black hole can put an almost arbitrary amount of matter into the same space, therefore the gravitational pull is factually much stronger than for any "ordinary" object of the same radius.

However she is saying the compression itself is already increasing the pull.

So as an example, suppose our sun got replaced by a black hole of identical mass (but much smaller radius). Would this cause orbits of the planets to shrink (increased gravitational pull) or stay the same (identical gravitational pull)?

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@_jal 8 days

Replying to @nsoonhui 🎙

"Io, corner pocket."

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@DerekBickerton 8 days

Replying to @nsoonhui 🎙

    ♩ ♪ ♫ ♬
    Black hole sun, won't you come
    And wash away the rain?
    Black hole sun, won't you come?
    Won't you come? Won't you come?
    ♩ ♪ ♫ ♬
https://www.youtube.com/watch?v=efc7njKAfgo

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@bjt2n3904 8 days

Replying to @nsoonhui 🎙

One question I had, prompted by a fever dream in which a black hole spawned in my house...

If a black hole were to come into sustained existence, assume the smallest one. How long could we stand near it before being unable to escape? And how far is that distance?

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@gradschool 8 days

Replying to @nsoonhui 🎙

I admit I know next to nothing about this stuff, but something doesn't add up. If everything has a Schwarzchild radius determined by its mass, then should we conclude that particles like electrons and protons also have a (very small) Schwarzchild radius? If the smaller it is, the sooner it explodes, then shouldn't atomic particles have all finished exploding a long time ago? When they explode, what do they eject, if not more subatomic particles like themselves? Alternatively, is the explanation that atomic particles are extended bodies whose sizes exceed their Schwarzchild radii instead being of point masses? If so, then what kind of stuff fills the interior of an electron? I don't have any answers but I have a feeling we're on shaky ground when we start trying to extrapolate general relativity concepts to atomic scales.

edit: typo

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@techdragon 8 days

Replying to @nsoonhui 🎙

Surprised no one has mentioned the Kugelblitz yet, so I’ll drop this fun hit of exotic theoretical engineering here.

https://en.wikipedia.org/wiki/Kugelblitz_(astrophysics)

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@sidlls 8 days

Replying to @nsoonhui 🎙

One of my favorite science fiction stories, "The Krone Experiment", has this question as a central plot element. https://www.goodreads.com/book/show/16032842-the-krone-exper...

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@daniel-thompson 8 days

Replying to @nsoonhui 🎙

This is the kind of question that makes me believe in the Great Filter¹.

¹https://en.wikipedia.org/wiki/Great_Filter

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@PaulHoule 8 days

Replying to @nsoonhui 🎙

If a ‘Type III’ civilization is meaningful it could be one that uses a quasar the way we use a star.

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@Mizza 8 days

Replying to @nsoonhui 🎙

When I was a kid I was really afraid that particle colliders would create a black hole that would sink to the center of the earth and eventually eat us all, so I find this article quite soothing.

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@badrabbit 8 days

Replying to @nsoonhui 🎙

I think this discussion is too focused towards stable blackholes. How useful can unstable (even nanosecs) blacholes be?

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@andrekandre 8 days

Replying to @nsoonhui 🎙

  > Slight problem with this is that you can’t touch black holes, so there’s nothing to hold them with. A black hole isn’t really anything, it’s just strongly curved space. They can be electrically charged but since they radiate they’ll shed their electric charge quickly, and then they are neutral again and electric fields won’t hold them. So some engineering challenges that remain to be solved. 
im not even sure how to begin there... probably the only wait contain a black hole would be... warping space-time negatively? like kind of warp bubble?

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@doodlebugging 8 days

Replying to @nsoonhui 🎙

I remember back in the day when cartoons had black holes you pull out of a pocket and throw down to use either as a portal to a different part of the cartoon or as a way to send your antagonists somewhere else.

I think that's where we should start in looking at potential use cases for personal, instant black holes.

I'm not young any more so I would volunteer to help in development and testing of any portals as long as I get good Cajun coffee and a smoked brisket sandwich in the lunchbox with a blood orange and a slice of Mom's apple pie.

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@xwdv 8 days

Replying to @nsoonhui 🎙

It’d be cool if we made a black hole type bullet that would suck someone or something in completely on impact and dissolve. Not sure if feasible though.

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@nyc111 8 days

Replying to @nsoonhui 🎙

> So, if you hold the mass fixed and compress an object into a smaller and smaller radius, then the gravitational pull gets stronger. Eventually, it becomes so strong that not even light can escape. You’ve made a black hole.

In Newtonian doctrine, a spherical object, like earth, attracts -as if- all its mass is concentrated at its center. So, if her reasoning is correct, the earth must already be a black hole, because all its mass is supposed to be concentrated at its center.

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@llIIllIIllIIl 8 days

Replying to @nsoonhui 🎙

Send trash in it.

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@dioramayuanito 8 days

Replying to @nsoonhui 🎙

Awesome

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@ck2 8 days

Replying to @nsoonhui 🎙

The horrible but obviously accurate answer is it would be weaponized.

This is what I worry about with fusion, it's not going to be used for free power for the world, it's going to be used to power war-machines.

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@bell-cot 8 days

Replying to @nsoonhui 🎙

Extremely Understated summary answer (to the first question), from the article:

> So some engineering challenges that remain to be solved.

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@Victerius 8 days

Replying to @nsoonhui 🎙

> Roger Penrose already pointed out in the early 1970s that it’s possible to extract energy from a big, spinning black hole by throwing an object just past it. This slows down the black hole by a tiny bit, but speeds up the object you’ve thrown

Black hole railguns/artillery?

Or, in the name of safety, mobile satellites in low earth orbit armed with hard tungsten rods, accelerated by temporarily generated black holes to relativistic velocities for prompt global strikes on time sensitive targets. Could make for a good movie.

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@gentleman11 8 days

Replying to @nsoonhui 🎙

> what could we do with it

Putin merely has access to nuclear weapons. I suppose the “I win or the earth gets it” is the same whether we’re talking nukes or a black hole

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@ajuc 8 days

Replying to @nsoonhui 🎙

Some other uses of black holes:

- space propulsion https://www.youtube.com/watch?v=oAocMzxPjjo

- colonization and energy source https://www.youtube.com/watch?v=Qam5BkXIEhQ

- weapons https://www.youtube.com/watch?v=zTMxO1nJaA4

I highly recommend the whole channel.

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@devoutsalsa 8 days

Replying to @nsoonhui 🎙

Not from the video… What blew my mind was to learn that a black hole get bigger when it absorbs light. Light from a campfire you had as a kid could be feeding a black hole right now.

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