We Aren't Even a Type One Civilization | David Kipping

Now, are you, have you also been interested in the issue of… this is a strange kind of science fiction-like issue. I've seen descriptions in the pop scientific culture online, I suppose, of the notion of different civilizational types. So, is that a notion that you've toyed with to any degree?

Yeah, this is probably the Kardashev scaling you're thinking of. So this is, Nikolai Kardash was a Russian Soviet Union physicist, I think in the '60s or '70s, and he wanted to try and come up with a way of classifying different potential civilizations out there. He argued that the most reasonable way to do this — and many people would disagree with him, I think — but he argued the most reasonable way would be energy usage.

He calculated that a Type I civilization, as he defined it, would be one that uses all of the irradiation that hits the planet. So, you know, imagine you cover the whole earth in solar panels, and they're 100% efficient solar panels, and the energy you collect equals the energy you use. So that would be a Type I civilization.

Now, in practice, you couldn't do it with solar panels, of course; you had nowhere to live. So you'd probably have structures in space to make this really work. But it's the energy usage which really matters. Going to a Type II is the energy of a star, and a Type III is the energy of an entire galaxy.

So there is interest; I think the reason why we like this is that if it's purely in terms of energy, we think we have a pretty good grasp on thermodynamics, and we think it's fairly immutable that any civilization must operate within the rules of thermodynamics. This places some fairly firm observational limits on how often this happens.

If there really were civilizations out there that were harvesting all the energy from their star, using it for work — so imagine like your laptop running; it produces still waste heat — and if you actually collected all the waste heat that it radiates, it'll be equal to the amount of power that goes in. It has to be an energy balance, conservation of energy, one of the laws of thermodynamics.

So we can look at these across the sky and see if there are stars which are essentially invisible in visible light because all that radiation is being absorbed but radiating in the kind of waste heat band — passes, which would be like infrared heat signatures.

And we've been looking for those, actually. A few weeks ago, there were a couple of candidates — seven candidates — that were announced by a group. They were scanning the sky looking for objects which had these anomalous infrared accesses. They're very interesting; however, another group soon after showed that three of these seven candidates happened to co-align with known radio sources, which they surmised were most likely background galaxies or things very far away that were covered in dust.

We know that galaxies often get covered in dust, and that can produce a similar type of signature to that which they see. So they argue that three of the seven are definitely false positives. In fact, when you run the numbers, it's perfectly possible the other four are too; just we haven't seen the galaxies yet. But the density of these objects, given the number of stars they looked at, looked consistent with them all being false positives.

So we don't have any compelling evidence for those objects, but it is nice that it's an observational test we can do. One of my colleagues, Jason Wright, led a survey out of Penn State where they surveyed 100,000 nearby galaxies to see if the entire galaxy had been converted this way. This is looking for what we call the Kardashev type III civilizations, and they found that, basically, there were no strong candidates.

So this is, you know, really intriguing. We look around, and we don't see nearby galaxies; after 100,000 of them do not appear. It's very rare that they appear to have been converted in this way, and similarly for many stars. About 100,000 nearby stars have been surveyed similar to this, so it's very curious.

It means that if civilizations do develop, they probably don't ever reach this Kardashev type II or type III. Maybe they go to the virtual world, you know. Maybe the idea of just developing with physical structures to add into an item doesn't make sense, and we all, you know, go into the metaverse, whatever it is, and just decide to live in a virtual world rather than the physical world.

Yes, well, in some ways that would be a more straightforward thing to do, obviously, because we're already doing that, and it's definitely less resource intense. So, yeah, what got you interested in your line of research? And you have about 100 papers, so why don't you outline first the full range of your research or at least the bulk of your research so that we can flesh out all the domains that we might discuss? And then, I'd like to know, you know, what it was that sparked your interest in what you're pursuing.

Yeah, thank you. So I work on many different things. My main area of research is exoplanets — so these are planets orbiting other stars we've been talking about thus far. And you know, that has always been a fascinating topic to me just because it was fairly new; only in the last 30 years have we been able to make this reach of being able to actually detect these things for the first time.

However, doing this… for me, when you look for exoplanets — certainly when I started looking for exoplanets — I would be immediately interested in the possibility of life and intelligent life that we've been talking about. Many of my colleagues would kind of giggle and laugh about that. It still carries what we call the giggle factor in the field of SETI, search for extraterrestrial intelligence. SETI is still something many of my colleagues kind of dismiss as a frivolous activity.

But for me, it's always been obvious that if we're going to look for stars which could have planets, and then we're going to look for planets that could have, you know, Earth-like conditions, then surely the endpoint of this entire intellectual exercise is to ask the question whether they have life on them. I don't understand what we're doing if we're not going to eventually shoot at that question.

So I was never shy of addressing that, and so a lot of my research has broadened out into questions of astrobiology, technosignatures, which is kind of a modern rebranding of SETI. It's about ways of looking for technology in the universe, such as the Dyson spheres that we've spoken about, and increasingly being interested in statistics and the application of statistics to these types of problems, where, as we've already pointed out, you're very data-starved.

We don't have a catalog of habitats out there, at least known habitats. We don't have a catalog of civilizations discovered thus far. So we are trying to make inferences about our uniqueness, which, to me, is one of the most interesting and fundamental questions we can ask: how special or common are we out there in the universe? We are trying to make inferences based off very little data, a parity of data, and to me that's always just been intellectually very stimulating to try and work on that fringe of where you know so little, but there's actually still some information there.

There is still something there. There's information about the timing of when Earth developed, when life developed on the Earth. There's information about the future of our planet; we know that from the evolution of the sun. There's information about the fact we don't see galactic empires.

So my job is to try to piece this puzzle together and not give necessarily definitive answers but at least limit the options down to what is the landscape of what’s possible.

Okay, so you mentioned that it's been about 30 years that we've had the technological capacity to even detect exoplanets, so do you want to talk a little bit about what that technology consists of when we started to discover these planets and then also how in the world do you, in fact, discover them?