Jupiter is about as likely to be one as I am to be thenextcurrent ruler of England ;)
... assuming, in fact, that you are not the current ruler of England.
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Jupiter is about as likely to be a Dyson Sphere as you are.
How do you know I'm not? I only play at being an illithid, you know.
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Jupiter is about as likely to be a Dyson Sphere as you are.
But, if the proliferation of monoliths achieve critical mass!
Much less likely. It's at least theoretically possible for you to the next ruler of England.
Jupiter is about as likely to be a Dyson Sphere as you are.
Nor do I see what plasma jets have to do with anything. Or why you'd have to be effectively inside the sun. The Dyson sphere surrounds the sun at planetary distance and captures all the energy output of the star, reradiating some of it (and probably missing some of the more exotic stuff like neutrinos). Plasma jets fallback in and are thus not "output". The energy they radiate is captured by the sphere, just like any other solar energy.
Trust me on this... it's about as theoretically possible for me to be the next ruler of England (which hasn't had a government since 1707) as it is for Jupiter to be a Dyson sphere.
Plasma jets have a lot to do with things because they do shoot out from the Sun on a regular basis, and are not unknown for stretching beyond Earth's orbit when they do (it's one of the reasons why there's been a lot of fear the Sun may randomly kill us). The temperatures typically tend, IIRC, to be about the same as that below the surface of the Sun. And most Dyson sphere proposals put them at about Earth-orbit distance or closer.
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Uhhhh... If you were to build a Dyson sphere... And that's an if on the order of, say, Mass Effect being accurate in every detail for the years it's set... Then the resilience of the thing kind of makes the plasma flares a minuscule problem. See... Every point on the sphere is under completely ridiculous stress, all the time, plus it needs to survive intact every coming comet/asteroid strike... Yeah. It would have to be one tough cookie. Plasma flares are a minor problem.
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You're welcome.
Uhhhh... If you were to build a Dyson sphere... And that's an if on the order of, say, Mass Effect being accurate in every detail for the years it's set... Then the resilience of the thing kind of makes the plasma flares a minuscule problem. See... Every point on the sphere is under completely ridiculous stress, all the time, plus it needs to survive intact every coming comet/asteroid strike... Yeah. It would have to be one tough cookie. Plasma flares are a minor problem.
That's why you don't build a solid shell, but instead have a "shell" made up of a cloud of orbiting power-gathering stations ;)
That concept is sometimes called a 'Dyson swarm', if that helps clear up the conversation.
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That concept is sometimes called a 'Dyson swarm', if that helps clear up the conversation.
It does, but it also immediately brings to mind a filthy joke with the punchline, "A proper amount of suction."
Speaking of suction, I always thought a Dyson Sphere was that ball the vacuum rides around on instead of the little wheels, but I don't concern myself all that much with the house-staff's equipment.
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Uhhhh... If you were to build a Dyson sphere... And that's an if on the order of, say, Mass Effect being accurate in every detail for the years it's set... Then the resilience of the thing kind of makes the plasma flares a minuscule problem. See... Every point on the sphere is under completely ridiculous stress, all the time, plus it needs to survive intact every coming comet/asteroid strike... Yeah. It would have to be one tough cookie. Plasma flares are a minor problem.That's why you don't build a solid shell, but instead have a "shell" made up of a cloud of orbiting power-gathering stations ;)
Well, not quite, apparently. The stations would not be satellites, because they would not be able to orbit anything due to making up a sphere in three dimensions. Instead, they would have to be stationary objects with their own engines. They call them statites. The problem here is transferring their power where it's needed, which is admittedly easier on a shell. But, if you already need to do this, you gain more if you keep the statites closer to the sun. So, the scenario is the one from Accelerando.
Uhhhh... If you were to build a Dyson sphere... And that's an if on the order of, say, Mass Effect being accurate in every detail for the years it's set... Then the resilience of the thing kind of makes the plasma flares a minuscule problem. See... Every point on the sphere is under completely ridiculous stress, all the time, plus it needs to survive intact every coming comet/asteroid strike... Yeah. It would have to be one tough cookie. Plasma flares are a minor problem.
It wouldn't even take a meteor strike, unless you built the thing from scrith. A Dyson Shell is basically a spherical pressure vessel 1 AU in diameter with an internal pressure of (IIRC) ~1N/m^2.
In addition, Larry Niven said that building a Ringworld is, in practice, akin to building a suspension bridge with no ends. Hate to see what building a shell is like.
In addition, Larry Niven said that building a Ringworld is, in practice, akin to building a suspension bridge with no ends. Hate to see what building a shell is like.
Depends on the sphere: The ringword is like a suspension bridge because it is spinning for centipetal/centrifugal 'gravity'. If you spin the sphere, you get gravity around the 'waist', and the math is rather more complicated than a suspension bridge.
If you don't spin the sphere, then it's like building a dome with no base, and the stresses are much less, because solar gravity pulling inward on a sphere, uniformly, is not nearly as strong as a earth-surface gravity outward, around the waist.
Actually, the inside of the sphere would have no gravity toward it. So, habitats would need to be on the outside... but that's a dark existence.
Actually, the inside of the sphere would have no gravity toward it. So, habitats would need to be on the outside... but that's a dark existence.
Not if you had solar freakin roadway hexes on every bit of the inside of the dyson sphere.
They could power gravity generators too.
Hrmm. A Dyson sphere isn't gravitationally stable, either.
I mean, it's not particularly unstable: the gravitational forces from within the sphere cancel out, which means that the overall gravitational influence of the sun cancels out too.
But if the sphere and the sun have any relative velocity, the sun will eventually collide with the inside of the sphere. So add 'big honking attitude jets' to the engineering problems to solve.
"big honking" doesn't even begin to describe it. =)
Indeed, nobody said it would be easy. A shell with a radius of 1 AU is something that definitely requires ultra-tech... but at that point, it is quite probably not useful anymore either. The engineering problems are beyond insurmountable. Today, we aren't even able to make a space elevator.
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Hrmm. A Dyson sphere isn't gravitationally stable, either.
I mean, it's not particularly unstable: the gravitational forces from within the sphere cancel out, which means that the overall gravitational influence of the sun cancels out too.
But if the sphere and the sun have any relative velocity, the sun will eventually collide with the inside of the sphere. So add 'big honking attitude jets' to the engineering problems to solve.
But is it a dyson sphere without a star, yet making use of the gravity of its own shell thus gravity being even without spin?
But is it a dyson sphere without a star, yet making use of the gravity of its own shell thus gravity being even without spin?Hrmm. A Dyson sphere isn't gravitationally stable, either.
I mean, it's not particularly unstable: the gravitational forces from within the sphere cancel out, which means that the overall gravitational influence of the sun cancels out too.
But if the sphere and the sun have any relative velocity, the sun will eventually collide with the inside of the sphere. So add 'big honking attitude jets' to the engineering problems to solve.
No. It's just a giant ball of gas.
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No. It's just a giant ball of gas.But is it a dyson sphere without a star, yet making use of the gravity of its own shell thus gravity being even without spin?Hrmm. A Dyson sphere isn't gravitationally stable, either.
I mean, it's not particularly unstable: the gravitational forces from within the sphere cancel out, which means that the overall gravitational influence of the sun cancels out too.
But if the sphere and the sun have any relative velocity, the sun will eventually collide with the inside of the sphere. So add 'big honking attitude jets' to the engineering problems to solve.
No, it appears to be a ball of gas, but we dont know if the centre is an ultra dense shell sufficient in mass to attract a gaseous outer layer or a solid core of a brown dwarf.
No, it appears to be a ball of gas, but we dont know if the centre is an ultra dense shell sufficient in mass to attract a gaseous outer layer or a solid core of a brown dwarf.
Have you any more evidence for "an ultra dense shell sufficient in mass to attract a gaseous outer layer" than I do for "a lemon pudding"?
Have you any more evidence for "an ultra dense shell sufficient in mass to attract a gaseous outer layer" than I do for "a lemon pudding"?
No, it appears to be a ball of gas, but we dont know if the centre is an ultra dense shell sufficient in mass to attract a gaseous outer layer or a solid core of a brown dwarf.
It's a cabbage! A gigantic galactic cabbage!
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It's a cabbage! A gigantic galactic cabbage!Have you any more evidence for "an ultra dense shell sufficient in mass to attract a gaseous outer layer" than I do for "a lemon pudding"?
No, it appears to be a ball of gas, but we dont know if the centre is an ultra dense shell sufficient in mass to attract a gaseous outer layer or a solid core of a brown dwarf.
Well, Jupiter's core is made of diamond, so a gigantic galactic diamond cabbage.
But is it a dyson sphere without a star, yet making use of the gravity of its own shell thus gravity being even without spin?
There is no gravity within a sphere of uniform thickness. I suppose you could make a dyson sphere heavy enough to have gravity on the outside surface, but why would you?
It would be easier and more pleasant to live around the equator of the sphere, spinning for centrifugal force, and using a glass ceiling to keep the air in.
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Now I have to go watch ST:NG "Relics".
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Dingmok and Pres Man at Tanagra.
Cosmo3PO, his eyes uncovered!
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Well.. if you're going to spin the thing...Then a Niven/Pournell ring is good enough, surely?
The original idea of the Dyson sphere and the Kardashev scale were about power, not living space. A full sphere lets you capture 100% of the star's energy output. Also, a sphere is more stable (more below).
As for making adjustments to the ring/habitat so that the central sun doesn't crash into it. I've always wondered (Other than the even more complexity being added) why some sort of adjustable mass balance wasn't included in Nivan/Pournell's idea?
Other than to make more 'good story' as it were. Much like Asimov's original laws of robotics.
It wasn't actually to make a good story: Niven assumed the Ringworld would be stable, because its vaguely like an orbiting object. A bunch of MIT students proved otherwise. Niven simply turned his retcon into a good story.
A ringworld really is unstable: when it is off center, the net gravitational forces serve to pull it further off center. A sphere is more stable, because having the star become off center doesn't make it become more off center.
As far as a 'mass balance', if you're trying to move something as massive as a ringworld or a Dyson sphere using gravitational forces, you'd need a correspondingly big mass to move around. Pushing the star around with its own magnetic field is probably easier in both cases.
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I think that's the most relative use of the word "easier" I have ever seen.
I need to re-read an old Niven article titled "Bigger than Worlds" about megastructures. It predates the revelation that the Ringworld is unstable, so I won't say that its perfectly accurate, but it does discuss a lot of weird ideas that are impractical for rather obvious reasons. Including a galactic-scale Dyson sphere. Or an Alderson disk.
Edit: Here's a version of it. The illustrations are gone, though.
