3 ms·

So this article started as a good intro and overview of the Fermi Paradox (which is somewhat of a misnomer because as far as Fermi was concerned it wasn't a par

by cletus 7y ago

So this article started as a good intro and overview of the Fermi Paradox (which is somewhat of a misnomer because as far as Fermi was concerned it wasn't a paradox at all) but it faltered at the end when it talked about habitable worlds. This is a topic Isaac Arthur [1] has gone into great depth about. If you haven't found his YouTube channel yet prepare to lose several days of your life. I find his arguments here compelling. Basically planets only matter as a source of raw materials. Planets are highly inefficient ways of creating living area. The most likely outcome for a spacefaring civilization is actually a Dyson Swsrm. 1% of Mercury's mass used this way could create orbiting habitats that support a quadrillion people and fully utilize the sun's power output (a so called Kardashev-2 or K2 [2] civilization). And these are simply O'Neil Cylinders [3], which don't require any materials that don't already exist. The beauty of this is it doesn't require much more technology than we already have. Better yet, it doesn't even require commercial nuclear fusion (personally I'm not yet convinced this is even viable). Take this further and a K2 civilization is not subtle and is highly detectable. For it not to be violates thermodynamics. We've seen no evidence of any K2 civilizations within millions of light years, which suggests their existence is highly unlikely (within the cone of spacetime we can observe). Given this seems to be such a natural evolution you can extrapolate and say that we are pretty much alone. Remember it's not about what most civilizations do because it only takes one to go this road. The argument that no civilizations become K2 civilizations use much harder to swallow than a few do. This notion gets more absurd the more civilizations there are. [1]: https://www.youtube.com/channel/UCZFipeZtQM5CKUjx6grh54g https://www.youtube.com/channel/UCZFipeZtQM5CKUjx6grh54g [2]: https://en.wikipedia.org/wiki/Kardashev_scale https://en.wikipedia.org/wiki/Kardashev_scale [3]: https://en.wikipedia.org/wiki/O%27Neill_cylinder https://en.wikipedia.org/wiki/O%27Neill_cylinder

BurningFrog 7y ago
I've never heard of K2 before. Really interesting! I suppose one reason we can't see them is that there is an even better model so advanced civilizations end up using, but we haven't figured it out.
Balgair 7y ago
These are all under our current understanding of physics, which does a good job, but we know it's not the full picture. Matter, the stuff you and I are made of, is ~5% of the universe's mass-energy. We understand the physics of this stuff fairly well. Dark Matter is, as far as we can tell, is entirely made of stuff that falls down and does nothing else. Dark Matter is ~25% of the universe. We have a fair few theories of what Dark Matter is, if/how we can use it, how to make it, move it, etc, but it's still very active research. We have a toehold on Dark Matter. Dark Energy, which makes things fall up, is ~70% of the universe. We are almost completely stumped as to what it is and how it works beyond making the universe roomier. We're just totally knackered on Dark Energy. Any civ that is thinking that seriously thinking about (let alone putting down-payments on) discombobulating planets in order to make more lawns to mow and gardens to weed is very likely to have more than a toehold on Dark Matter and is likely trying to make Dark Energy levitate tequila shots. And that's just the physics that we know we're missing. K2 civs are probably far more aware of yet more dragons in the mists. So, concluding (correctly) that since we don't see the IR heat of K2 planet demolitions, that we're alone, is not the best conclusion. We've not a clue as to what the rules of the universe are yet. We can talk about strategy once we learn how the knights and bishops move about the board.
lend000 7y ago
While I love futuristic ideas like those of Dyson, it seems naive to assume that because we don't see evidence of our virgin civilization's futurists' visions of advanced civilization, it does not exist. This is considering that our futurists are currently living in a newborn civilization on a geological time scale and are still grounded in their vision by science that we currently have. I'm of the opinion that we should probably wait a few thousand (or perhaps million) years before we start slapping the word "law" onto some reliable physical properties we can recreate in little Earth-scale experiments. And since we don't know for certain whether there is advanced life or not, we also don't know what the universe would look like if there was -- perhaps the current stars we see are just a fraction of the stars that existed pre-Dyson swarming.

by cletus 7y ago

BurningFrog 7y ago

I've never heard of K2 before. Really interesting! I suppose one reason we can't see them is that there is an even better model so advanced civilizations end up using, but we haven't figured it out.

Balgair 7y ago

These are all under our current understanding of physics, which does a good job, but we know it's not the full picture. Matter, the stuff you and I are made of, is ~5% of the universe's mass-energy. We understand the physics of this stuff fairly well. Dark Matter is, as far as we can tell, is entirely made of stuff that falls down and does nothing else. Dark Matter is ~25% of the universe. We have a fair few theories of what Dark Matter is, if/how we can use it, how to make it, move it, etc, but it's still very active research. We have a toehold on Dark Matter. Dark Energy, which makes things fall up, is ~70% of the universe. We are almost completely stumped as to what it is and how it works beyond making the universe roomier. We're just totally knackered on Dark Energy. Any civ that is thinking that seriously thinking about (let alone putting down-payments on) discombobulating planets in order to make more lawns to mow and gardens to weed is very likely to have more than a toehold on Dark Matter and is likely trying to make Dark Energy levitate tequila shots. And that's just the physics that we know we're missing. K2 civs are probably far more aware of yet more dragons in the mists. So, concluding (correctly) that since we don't see the IR heat of K2 planet demolitions, that we're alone, is not the best conclusion. We've not a clue as to what the rules of the universe are yet. We can talk about strategy once we learn how the knights and bishops move about the board.

lend000 7y ago

While I love futuristic ideas like those of Dyson, it seems naive to assume that because we don't see evidence of our virgin civilization's futurists' visions of advanced civilization, it does not exist. This is considering that our futurists are currently living in a newborn civilization on a geological time scale and are still grounded in their vision by science that we currently have. I'm of the opinion that we should probably wait a few thousand (or perhaps million) years before we start slapping the word "law" onto some reliable physical properties we can recreate in little Earth-scale experiments. And since we don't know for certain whether there is advanced life or not, we also don't know what the universe would look like if there was -- perhaps the current stars we see are just a fraction of the stars that existed pre-Dyson swarming.