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Astronomers are on the Hunt for Dyson Spheres (www.universetoday.com)

submitted 5 months ago by [email protected] to c/[email protected]

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[–] [email protected] 2 points 5 months ago (1 children)

I don’t think you have any appreciation for just how much energy even a dim star provides. A Kardashev 2 civilization has access to a billion times the energy we (Earth) have, and we only use about 70% of the energy we have access to.

We also have no idea what such large amounts of energy could be practically used for. Just as one possible example, the recent approach for warp drives would consume large amounts of energy - and it would cause the energy to be used over a large area, going against your assumptions. Of course there are many other options, e.g. creating matter from energy.

Even if you use all that energy, there will still be waste heat.

Yes, and as I keep repeating, the waste heat would not necessarily be produced at the location of the Dyson sphere.

Now you’re proposing that this hypothetical civilization has a second star (at least) that it’s importing energy from, which means it will be a larger area emitting infrared in their home system, because thermodynamics still has to be obeyed.

First: why must there necessarily be a second star? They could live inside ships in-between solar systems, which would only need one star to import energy from, and no more. And my whole point is that this would make the Dyson sphere itself much dimmer than you're assuming it to necessarily be.

And yes, the laws of thermodynamics have to be obeyed. They are as rigid as the speed of light, meaning there might be shortcuts but they are very advanced. To put it in perspective, we are almost capable of starting a Dyson swarm, and we have no options for bypassing the laws of thermodynamics and only have the barest ideas of how to bypass the speed of light

You haven't shown that the laws of thermodynamics actually pose limits here. Nothing I'm proposing goes against the laws of thermodynamics.

[–] [email protected] 1 points 5 months ago (1 children)

Sorry, all I'm seeing are reasons how you could take all the energy from a given star and move it elsewhere without a reason to do so, even to the point where virtually none of that energy is being used locally. This is the classic solution looking for a problem idea.

There are plenty of resources on the internet that have already responded to all your questions. Feel free to look it up.

[–] [email protected] 2 points 5 months ago (1 children)

Yes, I was only focusing on the "physically possible" part. I don't think it makes sense for us to inherently limit our search for such things to the most obvious solution - focus on that first, sure, but don't rule out that non-physically based assumptions are wrong. We can't assume that a civilization capable of producing a Dyson sphere would exactly follow what we assume to make the most sense.

But I can gladly provide some possible reasons:

A dark forest scenario would mean that you'd want to hide your energy harvesting as much as possible, while also not living close to megastructures that could be discovered from afar
A civilization focused on exploring surrounding star systems would automatically spread their energy usage around a wide area
They could be building things they don't want lower civilizations to see (e.g. prime directive), which would necessitate building them in voids (as long as they don't have technology to cloak it)

You're writing as if the assumption of local energy usage is physically given and can't be wrong, but we simply can't know for now. It could be right, or it could be wrong. Again, I agree that it makes sense to assume it to be correct, as it would be a much more easily recognizable marker, but that doesn't mean it's the only option.

[–] [email protected] 1 points 5 months ago (1 children)

Yeah, if you're going dark forest and AI, you could do a lot with even a K1 civilization, which makes a Dyson swarm kind of silly, anyway. Unless you put the effort into it, in which case it would be difficult to effectively fight a K2 civilization, especially a multi-system one, because the power, numbers, and capability to spread make options other than hiding not make much sense, anyway. Throw in some Von Neumann probes for good measure and the only winners will be the ones who spread faster.

The Bobiverse gives some ideas about what some good probes can do, and the Culture gives some ideas of just the kind of power an advanced civilization can have. Darwin's Radio has some good ideas about the dark forest and interstellar wars/genocide, and some interesting ideas about the nature of reality and matter itself.

[–] [email protected] 1 points 5 months ago

Yeah, if you’re going dark forest and AI, you could do a lot with even a K1 civilization, which makes a Dyson swarm kind of silly, anyway. Unless you put the effort into it, in which case it would be difficult to effectively fight a K2 civilization, especially a multi-system one, because the power, numbers, and capability to spread make options other than hiding not make much sense, anyway.

I'd argue that the Dyson sphere is a method of hiding your whole solar system if done right - you put out your torch, which reduces the likelihood of visual detection, while also being able to safely expand your civilization throughout your solar system. Von Neumann probes would probably be a terrible idea in a dark forest scenario, since their communication should come back to you, spreading your position far and wide.

The Bobiverse gives some ideas about what some good probes can do, and the Culture gives some ideas of just the kind of power an advanced civilization can have. Darwin’s Radio has some good ideas about the dark forest and interstellar wars/genocide, and some interesting ideas about the nature of reality and matter itself.

Thanks for the recommendations!