Methods to turn a black hole into a energy source?

[Whack-a-Mole]

@Chronos

Eh, Jupiter’s gravity well isn’t all that useful, since to get down into Jupiter’s well, you first have to get up out of Earth’s well, as well as further up away from the Sun. The surface of the Earth is probably at a lower total gravitational potential than Jupiter. But in any event, none of them are at all even remotely significant compared to the gravity well of a black hole.

Well, I presume to get to use a black hole we’d need to get out of Earth’s gravity well just the same.

Unless we make a black hole on earth but then would that have sufficient gravity to be useful as mentioned without killing the earth?

[billfish678]

@ivn1188

A “laboratory sized” black hole will not have significant gravity above the nano-scale event horizon. How would this provide energy?

Which relates to something I meant to bring up in the other thread.

If a black hole is small enough (and even a small one is pretty damn massive), can you even feed/force enough matter into it to be useful?

I mean, if the darn thing is atom sized, how many atoms per second can you get it to suck down?

At some point its going to be small enough (and still pretty massive) that even if the conversion efficiency from matter to energy is 100 percent, the total output per unit time aint going to be that impressive.

And, if its the kind of blackhole that evaporates, at some point, the evaporation rate (inverse to its size) and the limit to how fast you can cram matter down it means you won’t be able to “keep it alive”…baring of course the possibility of small, inherently stable black holes.

[tim314]

@Whack-a-Mole

Well, I presume to get to use a black hole we’d need to get out of Earth’s gravity well just the same.

Unless we make a black hole on earth but then would that have sufficient gravity to be useful as mentioned without killing the earth?

If you go back to the thread that inspired this one (linked in the OP), you’ll see that the black holes Chronos has in mind are ones that would be created in a laboratory.

Under certain scenarios a black hole could be produced at the Large Hadron Collider. (Of course since the LHC is exploring new regimes of physics, we don’t know if these scenarios actually occur in the real world.) Some people get pretty freaked out by this prospect, but in fact there are a number of reasons why we can be certain it would pose no danger. For one thing, a black hole that small would radiate itself out of existence before it could cause us any problems.

Even more convincing, consider that cosmic rays with higher energies than those at the LHC have bombarded our planet many, many times. The fact that we don’t see any black holes proves that either (A) that energy isn’t sufficient to create them, or (B) any black holes created in this way don’t stick around long enough to be noticed.

In short, nature has conducted the experiment many times already and shown it to be safe.

[Whack-a-Mole]

@tim314

If you go back to the thread that inspired this one (linked in the OP), you’ll see that the black holes Chronos has in mind are ones that would be created in a laboratory.

Under certain scenarios a black hole could be produced at the Large Hadron Collider. (Of course since the LHC is exploring new regimes of physics, we don’t know if these scenarios actually occur in the real world.) Some people get pretty freaked out by this prospect, but in fact there are a number of reasons why we can be certain it would pose no danger. For one thing, a black hole that small would radiate itself out of existence before it could cause us any problems.

Even more convincing, consider that cosmic rays with higher energies than those at the LHC have bombarded our planet many, many times. The fact that we don’t see any black holes proves that either (A) that energy isn’t sufficient to create them, or (B) any black holes created in this way don’t stick around long enough to be noticed.

In short, nature has conducted the experiment many times already and shown it to be safe.

Sorry, I was unclear.

I know lab made black holes (ala the LHC) are not a danger in the suck earth into it notion.

I was thinking about the guy proposing attaching long rope to a generator and tossing the end of the rope at the black hole where it would suck in the rope and turn the generator.

In order to do that on earth I think you’d need something with a lot more gravity than the LHC kind of black hole and a black hole sufficient to pull off that idea would be a danger to the earth.

[tim314]

@Whack-a-Mole

Sorry, I was unclear.

I know lab made black holes (ala the LHC) are not a danger in the suck earth into it notion.

I was thinking about the guy proposing attaching long rope to a generator and tossing the end of the rope at the black hole where it would suck in the rope and turn the generator.

In order to do that on earth I think you’d need something with a lot more gravity than the LHC kind of black hole and a black hole sufficient to pull off that idea would be a danger to the earth.

OK, I see what you’re saying. Off the top of my head I’m not sure how big a black hole you’d need to make this practical. I’m also not sure a rope is the best idea, just because what do you do when you run out of rope? It seems like it’d be better to have something you could sustain indefinitely as long as you keep pumping in more fuel.

[Chronos]

Is this monopole-induced proton decay a generic feature of all GUTs? Or would it depend on how the forces are unified?

The details (like how long the lifespan is) depend on the specific model, but to the best of my knowledge, this is qualitatively a feature of all of the models.

I was thinking about the guy proposing attaching long rope to a generator and tossing the end of the rope at the black hole where it would suck in the rope and turn the generator.

In order to do that on earth I think you’d need something with a lot more gravity than the LHC kind of black hole and a black hole sufficient to pull off that idea would be a danger to the earth.

Yeah, I guess I’m kind of mixing my categories of holes. The mass-on-a-rope method wouldn’t be practical for a hole of the size the LHC might or might not produce, but it might be practical if we ever found a primordial hole floating around in the Universe with, say, the mass of an asteroid. One of those, we almost certainly couldn’t make from scratch, but they might already exist, and estimates vary wildly as to their numbers.

[Sage_Rat]

This still hasn’t really been addressed: Exactly how much energy would it take to create a black hole that would be large enough to not sizzle out? How much energy could be produced by that black hole within a period of ~100 years?