'Halo Drive' Would Use Black Holes To Power Spaceships (space.com) 157
A new study from researchers at Columbia University in New York suggests future spaceships could use black holes as powerful launch pads to explore the universe. The study "envisions firing laser beams that would curve around a black hole and come back with added energy to help propel a spacecraft to near the speed of light," reports Space.com. "Astronomers could look for signs that alien civilizations are using such a 'halo drive,' as the study dubs it, by seeing if pairs of black holes are merging more often than expected." From the report: Study author David Kipping, an astrophysicist at Columbia University in New York, came up with the idea of the halo drive through what he calls "the gamer's mindset." Using what he called a "halo drive" -- named for the ring of light it would create around a black hole -- Kipping found that even spaceships with the mass of Jupiter could achieve relativistic speeds. "A civilization could exploit black holes as galactic waypoints," he wrote in a study accepted by the Journal of the British Interplanetary Society and detailed online Feb. 28 in the arXiv preprint server.
The major drawback of a halo drive would be that "one has to travel to the nearest black hole," Kipping said. "It's akin to paying a one-time toll fee to ride the highway system. You have to pay some energy to reach the nearest access point, but after that, you can ride for free as a long as you like." The halo drive works only in close proximity to a black hole, at a distance of about five to 50 times the black hole's diameter. "This is why you have to travel to the nearest black hole first and [why you] can't simply do this across light-years of space," Kipping said. "We still first require a means to travel to nearby stars to ride the highway system. Kipping is now investigating ways to exploit other astronomical systems for relativistic flight. Such techniques "may not be quite as efficient or fast as the halo-drive approach, but these systems possess the deep energy reserves needed for these journeys," Kipping said.
The major drawback of a halo drive would be that "one has to travel to the nearest black hole," Kipping said. "It's akin to paying a one-time toll fee to ride the highway system. You have to pay some energy to reach the nearest access point, but after that, you can ride for free as a long as you like." The halo drive works only in close proximity to a black hole, at a distance of about five to 50 times the black hole's diameter. "This is why you have to travel to the nearest black hole first and [why you] can't simply do this across light-years of space," Kipping said. "We still first require a means to travel to nearby stars to ride the highway system. Kipping is now investigating ways to exploit other astronomical systems for relativistic flight. Such techniques "may not be quite as efficient or fast as the halo-drive approach, but these systems possess the deep energy reserves needed for these journeys," Kipping said.
Possible answer to why we don't see aliens (Score:4, Interesting)
Maybe at some point civilizations come across a promising technology (like black hole creation) and don't see some hidden danger until it is too late?
Re:Possible answer to why we don't see aliens (Score:4, Insightful)
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(note the lack of a
time dilation? (Score:2, Insightful)
That close to a black hole you get fantastic time dilation. After you move away, you find your whole civilization gone, or changed to something new.
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Careful, waving LASERs in the air is how you summon black helicopters.
It's an even better way of summoning regular helicopters, whereupon you're going to need a good lawyer.
Intergalactic Copyright Infringement (Score:2)
I believe the Romulans have prior art
Re: Possible answer to why we don't see aliens (Score:2)
Exactly. All we need to visit the stars is to catch us some of them black holes, bring them here, close to earth and away we go!
What is wrong with this picture? Why so dark? Who switched the light off??
There ain't no black holes nearby (Score:5, Insightful)
And it would take a lot of energy to make one
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Really? Can't we just have one single science or tech story without bringing up Trump on this site?
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Re:There ain't no black holes nearby (Score:5, Insightful)
I want to know how we're supposed to stop when we arrive at our destination.
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The same way anything we currently have stops in space. We just have to start the slow down a loooong ways out.
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That's what the Large Hadron Collider [wikipedia.org] is for. Duh.
Seems efficient (Score:5, Funny)
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Yeah, that seems like the major drawback. You are going to suffer beam spread and be exposed to an x-ray laser if you are anywhere near the sail.
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That's ok; that's about when we'll finally make it through the fifty years until viable nuclear fusion (hey, they didn't say that it was the *next* 50 years . . .)
hawk
FTL Photons Again? (Score:3, Interesting)
Let me get this straight. Photons would be fired toward the periphery of a black hole, so that they'd slingshot around and come back... faster than light? What?
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Re:FTL Photons Again? (Score:4)
Adding what form of energy? If it's adding kinetic energy, that means increasing the mass or speed of the photons. If adding more wave energy, that means increasing the amplitude of the wave, right? How would gravitational slingshot be able to increase mass or amplitude?
Re:FTL Photons Again? (Score:5, Informative)
Re: FTL Photons Again? (Score:1)
The margin here is too small to show thr proof, but I have decided a method of acheiving this effect without the six thousand year delay of a trip to the nearest black hole... Use two laser pointers instead.
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However, this black hole will have a stellar mass, so putting it on a ship makes little sense. Unless you want to move the whole star system, of course.
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Even in Newton's theory of gravity, photons are deflected from the Sun. Interesting, even some Physicists forget this! However there is a difference of a factor of 2 between the predictions of Newton's theory of gravity and Einstein's general relativity, in the amount of the affect.
https://briankoberlein.com/201... [briankoberlein.com]
[...]
The catch is that the amount of bending predicted by Newton’s model is half what Einstein’s model predicted. Eddington actually demonstrated not only that light was gravitationa
Fermi Paradox (Score:4, Interesting)
If this actually worked well, wouldn't we see halos around plenty of black holes, since other space-faring civilizations would be using the technique? Presumably enough laser light would be scattered by gravitational lensing or turbulence or whatever to be visible from here.
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This makes the assumption that space-faring civilizations exist, to which we have no evidence of. That said, if such a phenomenon were possible you are likely correct about the gravitational lensing aspect. The turbulence would very likely do a great job of mangling any beam of energy we send its way and turn it in a giant galactic light bulb.
Considering this, if that were likely the other question becomes... why are they not already galactic light bulbs? We see stars from great distances... should there
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Better summary (Score:5, Informative)
TFS doesn't say this, but the idea is to use spinning pairs of black holes. You shoot photons back, and by gravitational slingshot they come back with more energy, and they propel the vessel by hitting the sail.
Co-orbiting black holes, moving at relativistic speeds before their merger, are untapped batteries. There are an estimated 10 million black hole pairs in our galaxy.
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So if there are any spacefaring civilisations out there, they'll only be able to sail away from any black holes?
That cuts down on the places we should be looking, a little.
Fantasy physics... (Score:2, Informative)
It never ceases to amaze me at the amount of fantasy physics that occur in science. Take the classic "wormhole" concept where they fold a piece of paper and put pencil through it to imitate space being folded by phenomenon so that great distances can be traveled with little effort. It is entirely bunk, just like time, everyone knows it, but because they are enamored by the fantasy of it, they agree to it as a concept. Well here is a real physics check, collapsing that much volume (space is not actually e
Re:Fantasy physics... (Score:4, Interesting)
"It never ceases to amaze me at the amount of fantasy physics that occur in science" - I am bored by the number of morons who make this exact comment, oblivious to the myriad "magic" advances that were so recently fantasy.
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" to be a pendant."
My mom has a nice one, with a lapis lazuli in the middle. But what does jewellery have to do with anything?
Re: Fantasy physics... (Score:5, Insightful)
I don't think your hostility is warranted...
Firstly, we have no evidence that it's not possible to fold space to make wormholes, but we do have a pile of evidence that it might be possible, in the form of the mathematical models that keep getting tested and shown to actually match the way the real universe behaves. There have been plenty of experiments that take a form like "according to those models, if we find this object with X and Y parameters, it should also have Z", and when we actually stumble across an object matching those parameters, the model is confirmed at those parameters.
The speculative (not "fiction") part comes when we start looking at the edge cases of those models. What if we had a black hole that was extremely low mass, and compressed with forces stronger than gravity? What if its particles were entangled with those in another black hole? What if multiple black holes are arranged to produce a particular spacetime curvature to amplify other relativistic effects like time dilation?
For cases like those, the math works out, and shows weird results that we haven't observed in the physical world. That doesn't mean they aren't possible, but just might not be natural in conditions seen since the Big Bang. As humans, though, we excel at creating unnatural conditions. We can synthesize large quantities of unstable atoms, and trigger their decay with extreme precision. We can focus lasers to target single molecules. We can create beams of entangled particles and send them to locations a thousand kilometers apart, with enough surviving to perform further experiments.
Perhaps some day, we'll be able to engineer a way to directly test those edge cases in our models. Until then, they remain as open questions, best described as "apparently possible".
Now, as for your example...
Go ahead and wave your arms over your head. You've just warped spacetime, in a tiny and (for human technology at this time) immeasurable way. A record of your action is spreading out into the universe in the form of a gravitational wave, showing a slight shift in the position of your arm's mass. It took very little energy to move your arm, but you've actually deformed spacetime.
All of the physics involved in the preceding paragraph are measured and well-tested. Those tests allow us to gauge the scale of universal processes. It takes very little work to warp spacetime... literally just existing will do it. According to our models, though, we'd need a huge amount of deformation to create something like a wormhole. Multiply those scales together, and you end up with a problem on the larger side of "reasonable". It'll take energy levels somewhere between a nuclear bomb and a star (because estimates like this aren't exactly precise), but it's something humans could feasibly test before our extinction.
Once that test happens, one of two results will follow. Either we will have wormhole-creation technology and can go exploring the universe with wormholes as a tool, or we will have an observation that breaks our predicted models, and we'll have to create a new model that accounts for all of our observations. Either way, it'll be an exciting day for physicists.
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TLDR: A model is proof of nothing, have seen more than enough of them not predict any actual phenomenon and requiring me to disprove something that is not proven is not a good way to discuss Sciences.
"Firstly, we have no evidence that it's not possible to fold space to make wormholes,"
It becomes dishonest to require that I prove a negative for my arguments to have merit.
"but we do have a pile of evidence that it might be possible, in the form of the mathematical models that keep getting tested and shown to
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TLDR: You don't seem to understand science, logic, physics, or astronomy.
It becomes dishonest to require that I prove a negative for my arguments to have merit.
That's not actually true. Having a counterproof is a long-established and straightforward way to disprove something, and I simply note that you don't have any proof (in the form of a testable alternative model, for example) for your counterclaim (that folding space is impossible). It is dishonest to claim a negative, then hide behind the difficulty of proving it as a means to escape the burden of your claim.
Keep in mind evidence is not proof of anything
With apologies to Randall Mo [xkcd.com]
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"Light may NOT âoespeed upâ or âoeslow downâ it always travels the speed of light."
That statement makes you sound ignorant or COY in a vain attempt to entrap me. The speed of light is different based on the medium in which is is moving, meaning in laymans terms... it DOES speed up and slow down. Here watch this helpful YouTube video from FermiLab https://www.youtube.com/watch?... [youtube.com] you are in need of an education.
"Likewise, relatively and the time dilation effects have been experiential
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Re: Fantasy physics... (Score:1)
You didn't understand the folding paper analogy. No one said crumple the paper into a ball (blackhole). Bending the paper requires energy... but not as much as accelerating and slowing the pencil tip. And that energy is given back when it naturally "springs" back.
A reverse way of looking at this is to lay the paper flat. Then take the tip (spaceship) and draw a line from point A to point B. Draw it with enough force to use up the tip. At point B recollect the spread out graphine and reform the tip. Noth
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It never ceases to amaze me at the amount of fantasy physics that occur in science.
Well sometimes you look at what you have and try to see what you can accomplish. Other times you look at what you want and try to fill in the blanks. I want to live forever. Right now its a bleeding fantasy, we're all dying and there's nothing that indicates reversing aging, copying my brain to a computer or anything else is feasible in the 42 years statistics say a male of my age have left. I still want us to explore concepts that could make us live to be a thousand years old, not just a year or two more i
I'll let Einstein know... (Score:2)
"Take the classic "wormhole" concept... It is entirely bunk"
I'll let Einstein know you think he's a shithead next time I see him.
In the mean time I won't be taking my advice on science off some random on the internet.
Re: Fantasy physics... (Score:3)
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unless some other new technology like the EM drive were to be discovered
Speaking of fantasy physics....
The EM drive isnt a new piece of technology thats been discovered. It's a perpetual motion machine in disguise, i.e. complete and utter bunk.
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unless some other new technology like the EM drive were to be discovered
Speaking of fantasy physics....
The EM drive isnt a new piece of technology thats been discovered. It's a perpetual motion machine in disguise, i.e. complete and utter bunk.
They found the EM force was real, in once sense at least. It was actually the force on the wires leading to the apparatus -- hint, what happens to a wire carrying a current when it is in a magnetic field?
I have invented a starship drive that follows real Physics -- but, for practical purposes, requires impossible Engineering, at least for the foreseeable future (I recall Einstein was convinced that Gravitational waves that he predicted would never be detected!).
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I have invented a starship drive that follows real Physics -- but, for practical purposes, requires impossible Engineering, at least for the foreseeable future (I recall Einstein was convinced that Gravitational waves that he predicted would never be detected!).
I don't really follow your point. The EM drive didn't follow real physics. With far future advanced engineering it'd still be a perpetual motion machine.
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I have invented a starship drive that follows real Physics -- but, for practical purposes, requires impossible Engineering, at least for the foreseeable future (I recall Einstein was convinced that Gravitational waves that he predicted would never be detected!).
I don't really follow your point. The EM drive didn't follow real physics. With far future advanced engineering it'd still be a perpetual motion machine.
Please read the first paragraph of my post more carefully (the paragraph that you didn't quote). In essence, I said that that the EM drive did not work as advertised -- and although a force was measured, it was due to more pedestrian physics and the Earth's Magnetic field, hence not suitable as a Space Drive.
I suppose, I should spell things out in more detail for Americans (scary so many voted for Trump).
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Hmm...
On third thoughts, perhaps we could make use of the weak magnetic field between the stars???
Totally safe (Score:3)
Once you made it to the nearest black hole you can of course launch yourself in any direction, but if you ever want to change course you'll need to end up near another black hole. So this mode of transport basically involves aiming at a black hole over a distance of many, many light years, and then launching yourself almost directly at it. Don't forget to use your turn signal ;-)
Having said that, I'm in awe at the creativity that went into this.
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Slowing down (Score:3)
There's a much bigger problem with this, and every other idea for accelerating to relativistic speeds: how the heck do you slow down? It takes just as much energy to slow down, but when you're traveling that fast you shoot past the next pair of black holes before they can reduce your speed anywhere near enough.
Same problem as a light sail, which might work for acceleration as you build up speed near the sun but can't possibly work for deceleration since it's going too fast to collect enough energy from the destination star before it's gone.
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The neat thing about relativity is that even at relativistic speeds, your laser's photons will still travel at the speed of light relative to you. So it'd still work. Assuming it worked at all, and your end-point was near a different black hole of similar size, the delta-V/s decelerating should be the same as it was accelerating.
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That should work well:
Igor: aim my spaceship at that planetary system over there.
Jesus: Sure thing boss, write when you get there.
Igor: How long should this journey take, we'll need to how big to make the victuals room on our spaceship.
Jesus: Let me see...carry the 2...(divide by the speed of light * percentage of speed you'll be going)...about 20 years.
Igor: Okay, I think I'll just buy that dacha on the Black Sea.
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That destination star...just make sure you are pointed directly towards it, and you should get enough deceleration to stop before you splash down, right???
Good idea, not (Score:1)
And then your ship disappears into some hell dimensions, the crew rapes and tears each other apart and we end up gouging out our own eyes and shit.
Gamma rays? (Score:5, Interesting)
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I didn’t read the article
You must be a regular here! Who reads the articles anyway!
Not even bad space opera (Score:4, Interesting)
Just a few, teeny tiny problems:
1. So you need to be close to the black hole. Except for the very largest black holes, the tidal forces will rip you apart. See the answer to problem 3 in this exercise: [nasa.gov] solar mass black hole, distance roughly 30 times the radius, tidal forces on a human-sized object of 50,000g. Good luck with that.
2. Aside from that, they are relying on a "slingshot" effect for the laser beam. But the photons are already travelling at light speed, so they cannot speed up. They energy increase will go into frequency: you'll be transforming light into hard gamma radiation. Enough energy to accelerate you to relativistic speeds is more likely to simply vaporize your ship.
3. If you survive the tidal forces and the radiation and actually get to relativistic speeds, you're going to need to target another black hole to slow down, by reversing the whole process.
4. Meanwhile, you still have to travel interstellar distances by some other means, to get to and from the black holes.
This isn't science. It isn't even science fiction. Heck, I expect more realism in bad space opera.
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So you have two points, two problems of practicality and an unbased opinion. We already are using several techniques that when first dreamed up were beyond science fiction so the practicality problems can probably be solved. You should also look into the meaning of science, it's not about delivering working solutions at once and it needn't even be about something useful for human beings.
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hmm, now that you put it *that* way . . . so it's a simple matter of generating enough power to almost propel you at relativistic speeds, firing this co cent rated energy at something ng that warps space and time, and counting on properly handling the x-ray tase of even more power that you just aimed at your ship.
What could go wrong? :)
hawk
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What if you hit a tiny little rock floating in the void ..
Moot (Score:2)
#4 basically makes this a moot point regardless of if it actually is feasible or not (which is probably isn't).
Can't travel interstellar distances? That's easy, just slingshot around a black hole! Oh all black holes are fantastically far away? Well I guess you have to travel there conventionally (not feasible). Oh how to you stop at the other end? Well just use another black hole! Oh the other black hole isn't remotely anywhere near where you want to travel... Um well... Science and stuff.
I'm not sure impra
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Fermis Paradox explained (Score:5, Interesting)
I'm currently playing Elite dangerous and taking part in the Distant Worlds 2 expedition community event. 8 months across the Galaxy and back. 8 months.
And while I have an unrealistic space ship with a fictional "Frame Shift Drive" that can jump approx. 41 light years at a time after "collecting fuel" by flying around a sun at speeds faster than light for half a minute (just as unrealistic) I *still* need thousands of jumps and days to cover the radius of our Galaxy without stopping for vistas.
Frontier, the developers of Elite Dangerous, did some neat things in trying to be sort of scientifically correct with the representation of space and solar systems. And it has shown me one thing I wasn't fully aware of until now: the scales we're taking about when we talk about our solar system, our '''neighbor''' systems or let alone our Galaxy are so absolutely unbelievably big the words "large" or "huge" don't even fit in the faintest way.
Bottom line: I'm pretty sure somewhere out there civilizations exist, have existed and will exist. However, that we ever get to meet them or they us is, to be realistic, very very very unlikely. Like, I'd say, even orders of magnitude more unlikely that life and then intelligent life comes to exist in the first place. Life happens in extremely narrow margins at our scale as it is. That we get to change the laws of physics and get to travel around the system, Galaxy or even universe like we get to ride a bike is nice daydreaming, but it won't happen.
Not for us and not for others. It's pure physics and a game attempting to show the scale of our Galaxy can drive home the issue of scale and distances we're taking about.
We're alone and they are too. And it will stay that way until we fade.
My 2 cents.
Re:Fermis Paradox explained (Score:4, Funny)
You're lacking a sense of the scale of time. Once we're immortal and regularly going on million-year space expeditions, then it'll be more plausible. 8 months is nothing. We'll have pulsars sending out coded messages to uncontacted aliens to check out the local space diner long before entropy dissolves everything.
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[...]
We're alone and they are too. And it will stay that way until we fade.
My 2 cents.
I think that the probability of intelligent Life on other planets is near certainty, but that the probability interacting with intelligent Life on other planets is near zero.
Of course I'm excluding the possibility of any intelligent Life on Earth going to other planets. I'll refrain from discussing the existence, or non existence, of intelligent Life on Earth!
This is what the Romulans did. (Score:4, Interesting)
I hope it works out better.
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No, the Romulans used small "quantum singularities" they carried along with their ship. They fed the singularity with a matter stream, and captured the Hawking radiation that came out (this was my impression).
At least one ancient civilization (Score:2)
Discovered how to use black holes for time travel. But we won't hear more about them until 2020. The BBC are such bastards at times.
Is this VC clickbait? (Score:2)
Which lifeforms could use that? (Score:5, Insightful)
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Why, the Crystalline Entity, of course!
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Small thinking mistake in this hypothesis,... Which life forms - or complex matter of any kind - is able to survive the gravitational pull at a distance of only 50 times the radius of a black hole?
Presumably, the actual creatures wouldn't have to be there. It's not where the ship is, but the laser base that is shooting and collecting the lasers. I assume there is some diffraction effect on the laser around the black hole due to tidal forces that it needs to be that close to work as planned.
Re: Which lifeforms could use that? (Score:2)
Complex equipment. Or any complex matter, including anything that we would call biological or artificial life or equipment would be completely crushed due to the gravitational forces 'long time' before reaching the distance of 50 times the diameter of the black hole... Think: 'molecules destroyed' kind of 'crushed'.
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Presumably, the actual creatures wouldn't have to be there. It's not where the ship is, but the laser base that is shooting and collecting the lasers.
Complex equipment. Or any complex matter, including anything that we would call biological or artificial life or equipment would be completely crushed due to the gravitational forces 'long time' before reaching the distance of 50 times the diameter of the black hole... Think: 'molecules destroyed' kind of 'crushed'.
Quite possibly. However as Frank Lloyd Wright said when asked how his mile high building would actually support its own weight, "That's a problem for the engineers." This physicist has show that it is possible to leach this much energy off of a black hole in this manner, it's up to the engineers to make it actually work.
Talk about putting the cart before the horse (Score:3)
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How about we just start by building rockets and exploring the solar system a little bit before we start thinking about using black holes to get around space?
The same method could be used by collecting solar energy from our sun and turning that into a laser to transmit momentum to a space craft. Some testing has already been done and probably already possible to some extent in theory. The black hole method here is novel because it offers a percentage profit of energy more than what you put into it in a short amount of time. Assuming, of course, you've solved the engineering issues of creating the necessary laser transmitters and collectors that can function at t
Halo Drive ? (Score:5, Informative)
What a bunch of thieves.
The concept of a "Black hole driven starship" is called the Kugelblitz engine.
https://en.wikipedia.org/wiki/... [wikipedia.org]
Looking through the comments on a site *FOR NERDS* no one has brought this up yet. Shame.
So, to summarize... (Score:1)
Step 1: Find the closest black hole to your solar system (hopefully not that close)
Step 2: ?
Step 3: Profit
(Apologies to South Park)
Some remarks on photon sails (Score:3)
Dealing with relativistic speeds is an engineering problem, and not necessarily a difficult (at least when compared with other challenges of interstellar travel) one.
https://phys.org/news/2018-09-... [phys.org]
Deceleration with light sails is a solved problem, at least on paper. I'm not aware of any deployed examples.
http://ffden-2.phys.uaf.edu/21... [uaf.edu]
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hahaha, it's ALL on paper ignoring really difficult engineering problems. Your lights sails are going to be rendered into swiss cheese by the plasma explosions of micrometeorites passing through at 20% C
a solved problem, at least on paper.....bahahaha, you're not an engineer are you?
A question of time and itinerary (Score:2)
1. How long does it take light to circle the black hole of choice?
2. How are they planning to brake?
3. Do they plan to visit only blackholes, or is there a way to visit star systems inbetween too? Because once you stop (by some means) to look around, you're no longer near any black holes, so you're stuck.
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1. How long does it take light to circle the black hole of choice? 2. How are they planning to brake? 3. Do they plan to visit only blackholes, or is there a way to visit star systems inbetween too? Because once you stop (by some means) to look around, you're no longer near any black holes, so you're stuck.
1) Taking an arbitrary diameter of a large black hole multiply by 50, compare to the speed of light, and you get an answer of less than half a second.
2) The location near the black hole would presumably just be the point for the laser station. It would not only shoot a laser around the black hole to gain energy, but also shoot a laser at the ships solar sails to give it momentum. That laser would have a range much greater than 50 times the diameter of a black hole. Then you can do all sorts of tricks by bo
Instructions for Slowing Down (Score:2)
Answer: According to the article, you can propel up to a Jupiter-sized mass. Do you think a Jupiter-sized mass of fuel would permit you to slow down? Also, you only need to do that once, sending your Jupiter-mass to another binary black hole system and you've just created an interstellar highway between the two binary black holes and then you don't even need the fuel to slow down — you can slow down via rotating 180 degrees and sending a beam from the second black hol