What if we could use a Black Hole as starship?

[Fabien]

TL;DR

In the history, many have ipotized the space-time travel as something that could work at some necessary conditions...

What if the black hole's gravity were used while a spaceship was at the center of a black hole? If a mass reached the event horizon, time would appear to slow down for it, and reaching the center would take a long time, at least from the perspective of an outside observer, since the mass involved in that particular distortion of space-time would not be affected by the difference in the speed of time. However, if you were able to place an object directly at the center of the black hole, which appears to me like a whirlpool or a tornado: the gravitational force is exerted from the outside, and the time that the matter spends at the mercy of what could be called the "small-scale event horizon," or the space where the energy of tornadoes or whirlpools is most intense, then from the center, what could be called the "black hole's calm zone," then, since the black hole has sufficient mass and isolates the mass, or in this case, the spacecraft would have sufficient thrust to move from the inside, or rather from the center, making the spacecraft "surf" the fabric of space. I believe this is possible if:

1) We can insert the ship or mass into the center of the black hole without passing through its perimeter.

2) We create a "black hole magnet": a sort of control cabin to orient the black hole wherever we want. The concept can be simplified to the idea of a carrot hanging from a stick to make the donkey move in the desired direction. This involves a very high amount of energy, but since in the history of great innovations, such as gasoline, which is highly flammable and, despite the damage it can cause, is used to propel machines and engines, I propose the use of a singularity, a black hole that, as it is gradually generated, is consumed by the black hole, which is used to move through the fabric of space.

I haven't studied physics or mathematics, but I find the topic intriguing.

 

[Ibix]

I'm afraid this makes no sense at all. In no particular order:

• If you go into a black hole you never come out. No exceptions. If something goes into one it's not coming out. The maximum possible survival time inside a stellar mass black hole is 15$\mathrm{\mu s}$, rising to a bit less than an hour for a billion solar mass SMBH.
• "Time slows down near a black hole" is a severe oversimplification that is only true in limited senses.
• There is no "calm zone" in a black hole.
• Black holes don't have centers in the conventional sense - $r=0$ turns out to be more like a moment in time than a place.

Alcubierre's warp drive solution is a less implausible way of using GR to travel faster than light. It still requires energy condition violations, but it's the thing to study if you want to learn about semi-serious efforts at this kind of thing.

 

[DaveC426913]

TL;DR: In the history, many have ipotized the space-time travel as something that could work at some necessary conditions...

However, if you were able to place an object directly at the center of the black hole, which appears to me like a whirlpool or a tornado: the gravitational force is exerted from the outside, and the time that the matter spends at the mercy of what could be called the "small-scale event horizon," or the space where the energy of tornadoes or whirlpools is most intense, then from the center, what could be called the "black hole's calm zone,"

Sorry, this is what is commonly known as "word salad". It may be a fun idea to explore but it's not science, and PF does not allow speculative discussions.

 

[Baluncore]

To accelerate a starship, to the maximum speed, using a fixed energy, requires a starship with minimum mass. That is inconsistent with the extreme mass of a black hole.

 

[Fabien]

Sorry, this is what is commonly known as "word salad". It may be a fun idea to explore but it's not science, and PF does not allow speculative discussions.

Thank you for your message.

 

[Fabien]

To accelerate a starship, to the maximum speed, using a fixed energy, requires a starship with minimum mass. That is inconsistent with the extreme mass of a black hole.

I mean, a black hole could be the solution because its energy, through gravity, bends the fabric of space around it. I think it would be the quickest solution, but also, probably, one of the most dangerous. In fact, I've compared it to gasoline: it's a useful invention or discovery, but with several drawbacks.

 

[Fabien]

I'm afraid this makes no sense at all. In no particular order:

• If you go into a black hole you never come out. No exceptions. If something goes into one it's not coming out. The maximum possible survival time inside a stellar mass black hole is 15$\mathrm{\mu s}$, rising to a bit less than an hour for a billion solar mass SMBH.
• "Time slows down near a black hole" is a severe oversimplification that is only true in limited senses.
• There is no "calm zone" in a black hole.
• Black holes don't have centers in the conventional sense - $r=0$ turns out to be more like a moment in time than a place.

Alcubierre's warp drive solution is a less implausible way of using GR to travel faster than light. It still requires energy condition violations, but it's the thing to study if you want to learn about semi-serious efforts at this kind of thing.

Yes, a black hole attracts everything to itself. However, are we sure that nothing is immune to its gravitational attraction? After all, there's much we still don't know about our universe, just think of what our eyes can't see, and therefore isn't studied, or even theorized as existing...

 

[Fabien]

To accelerate a starship, to the maximum speed, using a fixed energy, requires a starship with minimum mass. That is inconsistent with the extreme mass of a black hole.

Why try to go faster than light if space can be bent from point (A) to point (B)?

 

[Baluncore]

Why try to go faster than light if space can be bent from point (A) to point (B)?

There is no escaping the fact that both point A and point B must be within the event horizon.

 

[Nugatory]

However, are we sure that nothing is immune to its gravitational attraction?

Depends on what you mean by “sure”?
The best current theory we have is General Relativity, and it says that a black hole of mass M has exactly the same gravitational field as the same amount of ordinary matter, and that it affects everything the same way. But are we sure that GR is correct? It could be wrong, if there is some as yet undiscovered new theory that:
1) Agrees with GR everywhere that we know, by observation, that GR is correct.
2) But disagrees with GR by predicting that there could be something that is immune to gravity in the vicinity of a black hole.
3) Is mathematically consistent with itself and is based on assumptions no less reasonable than those on which GR is based.

It’s impossible to prove that such a theory cannot exist, so yes, we aren’t “sure” that GR is correct. But unless and until someone can produce such a theory, there’s no reason to think that GR is incorrect. And that’s unlikely - maybe not as unlikely as discovering that the Earth really was flat all along and the observations suggesting that it is round and orbits the sun were optical illusion and experimental error, but close.

So that’s how sure we can be.

 

[Dale]

TL;DR: In the history, many have ipotized the space-time travel as something that could work at some necessary conditions...

What if the black hole's gravity were used while a spaceship was at the center of a black hole?

The idea of a black hole spaceship has been explored, but the concept is pretty different from what you describe.

https://arxiv.org/abs/0908.1803

The actual concept uses the Hawking radiation from a very small black hole for the propulsion. The gravity would not be useful for propulsion except as a slingshot.

And of course, crossing the event horizon is a catastrophic failure, not part of the operation.

are we sure

That isn’t a reasonable standard. “Do we have any evidence” or “do we have any reason to believe”. Or even “how confident are we”.

 

[PeroK]

I haven't studied physics or mathematics ...

Exactly!

 

[Ibix]

Yes, a black hole attracts everything to itself. However, are we sure that nothing is immune to its gravitational attraction?

We are absolutely certain that GR says that nothing is immune to gravity. There is no wiggle room there. And the only theory we have that predicts black holes is GR. So, as @Nugatory says, you'd need a new theory of gravity that matches every test we've ever done (deflection of light, gravitational waves, anomalous precession of Mercury, gravitational time dilation, to name a few) to high enough precision that we haven't noticed the difference, includes compact objects that look like black holes, but doesn't respect the equivalence principle in some cases. These are very strong bounds on what any alternative theory of gravity can look like.

If you also want it to be a curved spacetime theory, your restrictions are probably contradictory. The equivalence principle follows immediately from "gravity is curved spacetime", so requiring "gravity is curved spacetime" and "things can be immune to gravity" would seem to immediately rule out any possible theory.

After all, there's much we still don't know about our universe, just think of what our eyes can't see, and therefore isn't studied, or even theorized as existing...

Starting with "I wish there were unicorns" is not science and is unlikely to be productive. A theory might predict unicorns, or some experimental result might be better explained if there were unicorns, but neither of these apply here. Forcing a theory to conform to the existence of unicorns just because you'd like there to be unicorns isn't studying the world as it is, I'm afraid.

 

[PeroK]

Starting with "I wish there were unicorns" is not science and is unlikely to be productive.

However, it's so much easier to sit in a chair and dream about unicorns than to study physics. Think of all those nasty equations and all that hard work.

 

[anuttarasammyak]

Another orthodox way to make use of BH for travel. You happen to find a BH moving to your destination. You hitchhike and get off at your destination with designed time elapse as you like. Please take care that you should be energy rich to keep hovering above BH event horizon and will be alone due to pass away of all your people on the Earth.
[edit]
Satellite orbiting during the ride would be beneficial and comfortable with additional SR time dilation and zero gravity with centrifugal force.

 

[PeroK]

Another orthodox way to make use of BH for travel. You happen to find a BH moving to you destination. You hitchhike and get off at your destination with designed time elapse as yiou like. Please take care that you should be energy rich to keep hovering above BH event horizon and will be alone due to pass away of all your people on the Earth.

Just today I caught the 139 Black Hole from St John's Wood to Baker Street.

Well, actually, it was a London Transport bus, but same idea.

 

[javisot]

Another idea would be a traversable wormhole connecting two entangled black holes, one at a certain origin and the other at a certain destination. (Note: such wormholes don't exist, but it could work for a science fiction film)

 

[QuarkyMeson]

Yes, a black hole attracts everything to itself. However, are we sure that nothing is immune to its gravitational attraction? After all, there's much we still don't know about our universe, just think of what our eyes can't see, and therefore isn't studied, or even theorized as existing...

I think the other parts of this have already been covered, but I wanted to comment on the idea that there may be important things in the universe that our eyes cannot see and that science has therefore not studied.

The deeper physics probes into smaller length scales, higher energies, or more weakly coupled interactions, the harder and more expensive the relevant effects become to detect. An interaction that is extremely weak, very short-ranged, or suppressed by a high energy scale may require exceptionally sensitive instruments, enormous collision energies, or long observation times merely to establish that it exists.

Those same constraints also reduce the likelihood that such an effect could be exploited directly as a technology. There are important exceptions but an interaction too weak to produce a measurable effect on ordinary matter is generally also too weak to serve as a practical source of force, energy, propulsion, etc.

We have tested matter and its interactions to extraordinary precision. Phenomena do not need to be visible to the eye to be discovered, they only need to leave some measurable trace. In roughly four centuries of systematic experimental science we have identified electromagnetism, gravitation, and the strong and weak nuclear interactions, along with an extensive particle framework describing how matter behaves.

This does not mean that nothing important remains undiscovered. It means that experiments have already placed bounds on what additional particles and interactions can do. Whatever remains must either interact weakly, operate over very short distances, require unusually high energies, occur only under rare conditions, or mimic known physics closely enough to have escaped detection. We know far more about the space of physical possibilities than casual discussions often acknowledge.

Or at least we know enough to have an idea of where our ignorance is likely to lie.