The implications of an important 2023 paper have not been fully understood: it is possible most life in our universe is in the deep oceans of icy moons, orbiting planets that do not orbit stars
Thanks for writing this! It's a really interesting set of ideas. I'm left a little leery of the conclusion, however.
I think there are two big tensions in this essay. The first is along Jonathan's line of reasoning. It seems unlikely for water-based life to make black holes synthetically. Even if they eventually did so, that would likely be for power generations needs which would likely show up in ways that contradict the Fermi paradox?
Second, though, is this seems to contradict the whole thrust of your earlier essays about black holes and surface planets. The thrust of the https://theeggandtherock.com/p/holy-crap-ive-just-realised-that as far as I can tell is that because life generates a lot of black holes, universes which form life are likely to form. But then you mention here that "from an evolved-universe point of view, it doesn't really look as though the basic parameters of matter have been optimised by evolution to create the conditions for life on the exposed surfaces of rocky planets."
However, doesn't that push against your earlier thesis? The takeaway I got from the earlier essay is that it provides a better theory for why we exist than a hand-waved "anthropic principle." (And also explains better why there are very nice bubbles within a very hostile universe). But it almost leads to an anti-anthropic conclusion! If there's supposed to be a lot of life in the universe, and most of it is in water worlds, why aren't we?
Your closest explanation in this post is that this is actually a point of movement. We are an "old"-style life which is less efficient but was the first form to evolve in universes. This doesn't really respond to the anthropic-argument stuff, but I've always been uncomfortable with those types of arguments anyways. It definitely gives more of an explanation of why we're here, but it still seems a little just-so. Why is it that universes have been evolving away from that but there still happens to be just a couple (or even just one, fermi paradox and all) around?
[That still seems more likely than the universe just happening to have the right fundamental constants for matter etc.. But still poses a problem]
Yeah, I don't have a brilliant, confident answer to this one. But I do have cautious, tentative answers!
I do think that this universe seems fine-tuned to produce liquid water oceans (and thus life); it's just that the most energy-efficient way to produce and maintain them seems to be under the surface of icy moons. Which makes us unusual, sitting out on the surface of the only rocky planet in our solar system with liquid water oceans.
There are a few possible interpretations of that, and I gave one in the post: we might well be throwbacks to an earlier evolutionary era, when worlds like ours were the main source of life. But as the (more efficient) icy moons were optimised for, the conditions on worlds like ours were no longer optimised for. (There will always be these tradeoffs, as you move towards a fitness peak.)
There are other possibilities. We may have a valuable function, as air-breathing surface dwellers, who can reach space relatively easily. Who can make electronics and silicon computers and nanotechnologies and a whole bunch of things that are probably harder to make under water and ice. Including, ultimately, small black holes. Planets like Earth may be rare but nonetheless important cells inside the organism that is the universe.
That then begs the question: If we are so good at making technology (and thus small black holes), and icy moons are not, then why would the universe optimise for icy moons?
One possible answer is that the above assumption is wrong, and it's actually pretty easy to develop technology in these oceans under the ice, as easy at it is on Earth: we don't really have any idea what an intelligent civilisation would be capable of under those extreme conditions, nor of how those conditions may have been optimised by evolution to assist such civilisations. See, for example, my post on the metallic nodules on our own ocean floors, that we recently discovered might be acting as batteries and making oxygen. Totally unexpected, and happening in our own oceans.
Have you considered the opposite viewpoint, in that we are in a transition period, but in the opposite direction, from ploons to surface dwellers?
Firstly, core life is less likely to become space faring and therefore the number of black holes they will produce will likely be very limited.
Secondly, surface life forms earlier, universes should trend towards producing optimal size black holes earlier and earlier as evolution progresses.
Thirdly, it seems to me that the Goldilocks criteria means that surface planets are harder to create (more "complex"), which is also evidence that they represent a later form of evolution versus the more simple mechanism of ploons.
Finally, I won't deny that there's some element of wishful thinking that we humans are not some evolutionary dead end and evolution has designed us to survive and colonize the stars. If we are being replaced by ploons, that means that the evolutionary incentive is actually to kill us off as soon as possible to stop us from wasting available entropy.
Anyways, based on the above points, I think it's likely that ploons are actually the atavistic or backup method and surface dwellers like us are actually the current apex of cosmological evolution.
Thanks for the reply! I definitely agree with the broad strokes of your response. I don't have any particularly clever ideas, but I am curious about one thing:
If indeed we are throwbacks to an earlier evolutionary era, what other vestigial structures would be evidence towards that conclusion (other than our existence)?
I.e. part of your argument for the earlier phases is that even as evolution has moved away from immediate black holes as the primary reproductive mechanism, we still see black holes forming from dust clouds extremely fast. Ditto for star production and galaxies forming earlier than previously expected.
I suggest that there is a further line of thought indicated here: what are the necessary and sufficient conditions for the kind of life that can expand beyond its world of origin?
It seems to me that this requires the (probably rare) star-and-open-ocean origin (needs a catchy phrase for a name).
Life confined to water without a gaseous atmosphere won't develop mastery of fire or of electricity, at least in any scenario *I* can imagine. Without those, it won't develop mining, metallurgy, advanced tools, or spacecraft.
Also, how does such life further the evolution of the universe?
I am sure that many of us would welcome a future essay exploring this!
Best,
Jonathan
PS--If of interest, you might want to also explore the emergent DMT-verse; a domain in which PhD level researchers are now expressing confidence that there are repeatedly accessible dimensions with specific attributes. If correct, this would be yet another aspect of the evolving universe.
Good observations, and questions! I am extremely interested in this line of thought. I decided not to explore it in this post, because it was already too long. But I will definitely do so.
Yes, there are many limitations on underwater life. In fact John Smart (who has been very supportive of this project) has written about some of them. Here he is talking about that issue on Centauri Dreams, the forum for deep space news and ideas:
"So yes, many forms are possible, but only a few will be deeply accelerative, and thus dominate their environment, via competitive exclusion. Octopi could never reach our level even though they have two prehensile limbs and can build huts, because they can’t use tools and groups to dominate their environment. Water is too dense a medium relative to the force that can be generated by creatures made of protein. Cultural acceleration had to emerge first on land, etc."
So how life in the liquid water oceans of icy moons might further the evolution of the universe becomes an interesting question, in the absence of technology. I do feel that we have an air/land chauvinism that might blind us to some of the possibilities down in those depths. I don't think technology is impossible. I do think it would have to develop down very different channels. It’s a rich, complex subject, where I would have to speculate far more than in this post (which is fairly factual), so I’ll do it in a separate post.
And of course, life on icy moons and life on exposed surfaces may have very different roles to play. Maybe we are the ones who do the going out, the exploring, the connecting, and icy moon civilisations are inward. Maybe we bring them our technology.
I don't know! I would just be speculating. It's an area where I would need to think things through from first principles, and even then reality is too rich for me to be confident of my guesses. But please feel free to point me towards anyone else exploring this area, it does interest me enormously.
As for DMT, that’s a whole other world that I have not really explored. Again, please do point me at anything I should read.
Julian, If there's anyone I know who can come up with a plausible way that a technosphere could emerge amongst aquatic life, it's you. I'll look forward to your speculations! (I'm still waiting for someone to develop your ideas for "fire breathing dragons" into actual experiments! That really should be incorporated into some quality SF storytelling.)
Were such icy moon-based intelligent life to focus on inward development, I should think that, given the presence of the same biochemical pathways for production of DMT found in all tested mammals and certain non-mammalian animal species and plants, it is entirely plausible that such life would have access to it, possibly with the capability to concentrate it and even to titrate dosages. (They might have far more sophisticated control of what we call autonomic processes than do we.)
Perhaps the most visible researcher is Danny Goler. Here's a recent interview he did; significant as much for what he doesn't say as for what he does: https://youtu.be/NJp2rASRKMc?feature=shared
If you wish to converse with Mr. Goler, I have a close friend who's been exploring the DMT-verse and who knows him personally. I expect that I could arrange an introduction.
Awesome post, Julian! Two thoughts/ questions about the Hill sphere and tidal forces...
1. The hill sphere for free planets is much larger than for captive planets, but are there other limits on how far out a moon can be and still experiencel forces from eccentricity enough to create oceans? I guess it depends on the eccentricity more than the distance... My thinking is just that the hill sphere isn't quite the whole story re how many ocean bearing ploons you'd expect to find. (I guess the gravity of the ploons themselves could also help hear each other up? But not much, I'd have thought)
2. If you have a ploon orbiting a binary stannet, presumably the double-tidal forces there are even more effective at generating heat than around a single stannet? On the other hand, forming stable ploon orbits seems likely to be much harder around double stannets. I guess it doesn't matter for the theory as a whole but I wonder if you think that binary stannets would be over represented or under represented as hosts of ocean bearing ploons.
Yeah, you are quite right William, the Hill sphere is only part of the story. The gravitational friction drops off with distance – but it rises with with eccentricity, so there are tradeoffs.
The orbit of a moon that is further out from its planet will experience less tidal heating than will one that is further in. Likewise, a moon with a less eccentric orbit will experience less tidal heating than a moon that's (on average) the same distance out, but in a more eccentric orbit.
So moons much further out might require more eccentricity in order to have liquid water oceans.
The limiting factor there then comes from the fact that resonances help stabilise the eccentricity of the orbit – which matters, because without it orbits can be normalised, and slowly become more circular over time. But stable resonances require low to moderate eccentricities. So if a moon is too far out, and needs an extreme eccentricity to generate enough gravitational friction / tidal forces to keep its subsurface water liquid, then it can't really get into and maintain resonance with other moons. Well, they can GET into resonances, but it's just more unstable. Highly eccentric moons can transfer too much energy to each other on a close approach, destabilise the whole arrangement, and one might even get ejected from the system.
Also, really extreme eccentricity can mean the orbits of two moons overlap, which can lead to serious near-miss disruptions, or even collisions.
So yeah, the Hill sphere may be waaaaaay larger around a stanet than it is around a planet, but the zone in which ploons can maintain liquid water oceans will be considerably smaller than the full Hill sphere.
As for binary stanets... My initial gut feeling is that it would be much harder for ploons to find and maintain stable eccentric orbits in resonance with each other in a binary stanet system. They would have to be pretty close to one of the stanets, in order to not be destabilised by the other stanet, which would kind of take away the large-Hill-sphere advantage of not orbiting a star. (Or they would have to orbit the common gravitational centre of the two stanets – their barycenter – which would mean orbiting waaaay out from both stanets. Which would make it hard to generate enough gravitational friction to keep the oceans liquid.)
Buuuuuut these binary stanets, these JuMBOs (Jupiter Mass Binary Objects), seem to be orbiting each other at a very large distance. Far larger than is usual for, say, low-mass binary stars (which tend to tuck in pretty close to each other). So both of the stanets in one of these JuMBOs could have pretty large Hill spheres. Then again, as the stanets making up these JuMBOs have much lower masses than even low mass stars, I don't know how stable that binary is going to be longterm, at such large separation. Pretty weak gravitational binding. Maybe most of those binaries will separate as they age.
Basically, great question, and I'll have to research this more deeply!
I’ve wondered about the potential of "rogue planets", but didn’t think the answer would be so exciting.
There’s also a throwaway sentence in there –
"evolving away far more slowly than us" – that gets to an aspect of time, that I have wondered whether shouldn’t be added to the Drake Equation.
Is it possible that life and intelligence on Earth developed at turbo speeds, relative to what would be "normal" in the universe? Life clearly needs some balance of change and stability to evolve. The deep oceans of a ploon sounds like an environment where the necessary kind of change happens very slowly. Is it possible, then, that thanks to the particular tilt and spin of earth, the orbits of earth and moon, etc. our planet has run through relatively quick and stable iterations of change necessary for the evolution of life significantly faster than other life-supporting bodies?
I quite obviously don’t know what I’m talking about here, but it seems like an under-appreciated variable, seeing as how relatively small differences in speed of evolution should allow a late-starting planet to catch up with and surpass other planets or ploons that have been around for billions of earth years longer.
Yeah, I think you are right. The way energy is pumped into the Earth's geosphere, and biosphere – strong, rapid day/night pulses of energy, nested inside much longer winter/summer pulses – should lead to much more rapid chemical development, and then evolutionary development, on Earth that you would get in a colder, darker, less dramatically pulsed environment such as the liquid water oceans of an icy moon. I think evolution just has to happen slower in those depths. (But I may be wrong! If it's an environment optimised by evolution for the development of life, it could be surprisingly rapid due to non-obvious fine-tuned factors.)
The exposed surfaces of rocky planets seem to be higher risk, with higher instability, but also higher speed of development.
"An advanced civilisation that developed in a single, vast, subsurface ocean, beneath a crust of ice twenty or fifty or a hundred miles thick, may never even conceptualise a larger universe – an elsewhere – let alone explore it."
I know this was not the point of the essay but this smacked me very hard in the face, and I can't stop thinking about how, if true, this could position humanity (or Earth life generally, or maybe rocky planet life very generally) as having special access to the cosmos. And therefore, potentially, from an animist perspective, a special role in the universe a la "we are the cosmos coming to know itself"
Could that be a trait worth conserving, despite the relative inefficiency of creating conditions for rocky surface planet life? Could "coming to know itself" help direct future universal evolution somehow? Is there a cultural exchange between rocky surface planet life and icy sea moon life that kicks off the third stage black holes, so both types are needed for max optimization?
I think you might well be right, Alaina. It's a weakness in the piece, that I didn't explore the idea that our access to space (as air-breathers on the exposed surface) might be a feature, not a bug. I've been talking about this to a few people, and the feeling is, that humans (and other rocky planet surface dwellers, in other stellar systems) seem positioned to go out there and connect things in a way that water-dwelling, deep ocean civilisations, that developed under a hundred miles of ice, just won't be able to. Or want to.
So yeah, there may well be an evolved role for creatures like us. We are specialists in directly knowing the larger universe, and joining the dots metaphorically and physically. Those asteroids and comets can't just burst into life on their own. They need someone like us to come along.
A creature that evolved under a hundred miles of water that's under another hundred miles of ice is just not going to find it as easy to do that, for all kinds of reasons.
So yeah, we may indeed have a special role in the universe. Good!
> But our theory argues that intelligent, technology-wielding life in a universe helps that universe reproduce. (See this for more details
That theory is that black holes result in the creation of new universes that "evolve" parameters slightly different from parent universes. There was no explanation as to how "intelligent, technology-wielding life" would result in more such black holes rather than being a side effect of a universe which happens to produce such black holes.
> So that’s number 1, liquid water oceans, and number 2, heat. Icy moons beat rocky planets on both counts. Much more water, much more efficiently heated.
An efficient usage of a much smaller amount of energy can still result in less warm water than an inefficient usage of a FAR larger amount of energy. You would need to do a calculation of how much energy is available for life on rocky planets vs icy moons rather than just labeling one "efficient" and leaving it there.
> intelligent lifeforms wield technologies to manufacture artificially small black holes (for maximally efficient energy production)
That's what's missing from your linked post. But why would intelligent life do that? Wouldn't it be simpler to create energy via fusion on scales too small to create a black hole? Black holes don't release light as energy, they seem strictly inferior from the perspective of life outside of them.
In your other post you mention that Darwin didn't know about DNA as the mechanism for transmitting information from parent to offspring. That may be true, but he could observe the similarity in phenotypes (Galton was to make much of it in humans, and animal/plant breeders had noticed it earlier). We can't observe any such similarity, as we only observe our own universe. Instead of a stylized fact in need of explanation, you've got both an imagined/unobserved "fact" and a lack of explanation.
Tidal heating of planetary moons is the energy of the moon slowly becoming less excentric.
The molten moon core is not heated by pressure but by any _increase_ in pressure if the outer layers of the moon are slowly collapsing toward the center; no movement no increase in pressure, no heating. [The core may also be molten from the initial heat of formation and may be heated by decay of radioactive elements.]
Intriguing post. I think where the evolutionary logic may breakdown is the idea we can do probabilities on infinities. David Deutsch talks about this in his book Beginnings of Infinity in the context of the multiverse. The question is whether universe generation is a finite process with some fixed number of universes possible (in which case we can make the anthropic argument that we are more likely to find ourselves in a evolved universe as you describe), or if the number of universes is infinite, in which case we cannot argue the anthropic case. This is because you cannot say one infinite number is larger than another infinite number, they are both infinite!
New Reader. Thanks Marginal Revolution. Wow! (I haven't finished yet.) First the 'poster' of the moons is great. (I'm going to limit my exclamation marks.) Second, we should send probes to all the water moons. Finding other life would be huge. Maybe ask Musk to help? (Keep cost down.) Third about the unexpected planet forming regions; Have you heard about MoND? And are the regions in the mond regime? (local gravitational acceleration less than 10^-10 m/s^2.) Probably not, but it's worth asking I think. And finally I find some of your ideas to be a bit crazy... which is fine and fun, I have some crazy ideas that I love, but I try and remember that my crazy ideas are probably not true. (Which does nothing to stop me thinking about them... but somehow keeps me grounded...?)
The conventional Goldilocks story has a bunch of requirements that limit life: rocky planet, liquid water temperature, cleanup of bombarding rocks, protective magnetic field, nutrient recycling by tectonic activity, etc, and (I expect) a bunch more that we haven't figured out yet. Some of these may be soft edged, like they permit the evolution of slime but not much more. There are some interesting chemical ideas on the origin of life, but nothing is established so we don't know what the physical limits are. We are more at the how-could-it-even-work stage, rather than any kind of a clear understanding of what can and can't happen.
I see a reasonable case for oceans on moons and ploons but whether (eg) DNA works at 20,000 atmospheres - or whether there is actually an alternative to DNA that does work - is as far as I know an open question. It's possible to go glass half full and say evolution over an astronomical number of natural experiments will find a way, but it's also possible that one or more hard limits will rule out life of any kind in these seas. There's a bunch of unknown unknowns and some may be a big NO.
The evolution of higher brainy life is another giant step that won't happen anywhere. There was about 2 billion years when of only algae on Earth and it might have gone no further but for the high productivity of sunlit coastal zones that made predation of grazers an option. There's an interesting argument that there's an upper limit to viable brain development in the sea. Visibility is a matter of metres so there's not a lot of value in planning. You sit on a rock or at best swim around hoping to bump into something that you are able to eat rather than something that eats you. The smartest creatures in the sea evolved on land.
> or whether there is actually an alternative to DNA that does work
Isaac Asimov pondered different chemistries at different temperatures: http://www.bigear.org/CSMO/HTML/CS09/cs09p05.htm but from what I've heard, scientists since then don't think his other possibilities are viable.
Thanks for writing this! It's a really interesting set of ideas. I'm left a little leery of the conclusion, however.
I think there are two big tensions in this essay. The first is along Jonathan's line of reasoning. It seems unlikely for water-based life to make black holes synthetically. Even if they eventually did so, that would likely be for power generations needs which would likely show up in ways that contradict the Fermi paradox?
Second, though, is this seems to contradict the whole thrust of your earlier essays about black holes and surface planets. The thrust of the https://theeggandtherock.com/p/holy-crap-ive-just-realised-that as far as I can tell is that because life generates a lot of black holes, universes which form life are likely to form. But then you mention here that "from an evolved-universe point of view, it doesn't really look as though the basic parameters of matter have been optimised by evolution to create the conditions for life on the exposed surfaces of rocky planets."
However, doesn't that push against your earlier thesis? The takeaway I got from the earlier essay is that it provides a better theory for why we exist than a hand-waved "anthropic principle." (And also explains better why there are very nice bubbles within a very hostile universe). But it almost leads to an anti-anthropic conclusion! If there's supposed to be a lot of life in the universe, and most of it is in water worlds, why aren't we?
Your closest explanation in this post is that this is actually a point of movement. We are an "old"-style life which is less efficient but was the first form to evolve in universes. This doesn't really respond to the anthropic-argument stuff, but I've always been uncomfortable with those types of arguments anyways. It definitely gives more of an explanation of why we're here, but it still seems a little just-so. Why is it that universes have been evolving away from that but there still happens to be just a couple (or even just one, fermi paradox and all) around?
[That still seems more likely than the universe just happening to have the right fundamental constants for matter etc.. But still poses a problem]
Yeah, I don't have a brilliant, confident answer to this one. But I do have cautious, tentative answers!
I do think that this universe seems fine-tuned to produce liquid water oceans (and thus life); it's just that the most energy-efficient way to produce and maintain them seems to be under the surface of icy moons. Which makes us unusual, sitting out on the surface of the only rocky planet in our solar system with liquid water oceans.
There are a few possible interpretations of that, and I gave one in the post: we might well be throwbacks to an earlier evolutionary era, when worlds like ours were the main source of life. But as the (more efficient) icy moons were optimised for, the conditions on worlds like ours were no longer optimised for. (There will always be these tradeoffs, as you move towards a fitness peak.)
There are other possibilities. We may have a valuable function, as air-breathing surface dwellers, who can reach space relatively easily. Who can make electronics and silicon computers and nanotechnologies and a whole bunch of things that are probably harder to make under water and ice. Including, ultimately, small black holes. Planets like Earth may be rare but nonetheless important cells inside the organism that is the universe.
That then begs the question: If we are so good at making technology (and thus small black holes), and icy moons are not, then why would the universe optimise for icy moons?
One possible answer is that the above assumption is wrong, and it's actually pretty easy to develop technology in these oceans under the ice, as easy at it is on Earth: we don't really have any idea what an intelligent civilisation would be capable of under those extreme conditions, nor of how those conditions may have been optimised by evolution to assist such civilisations. See, for example, my post on the metallic nodules on our own ocean floors, that we recently discovered might be acting as batteries and making oxygen. Totally unexpected, and happening in our own oceans.
https://theeggandtherock.com/p/the-deep-ocean-floor-is-covered-in
So... maybe there's an evolved, fine-tuned chemical path to technological civilisation on the seafloor of icy moons that we are simply unaware of.
Ideas on this topic are very welcome. I do not feel I have a good final theory in this area.
Have you considered the opposite viewpoint, in that we are in a transition period, but in the opposite direction, from ploons to surface dwellers?
Firstly, core life is less likely to become space faring and therefore the number of black holes they will produce will likely be very limited.
Secondly, surface life forms earlier, universes should trend towards producing optimal size black holes earlier and earlier as evolution progresses.
Thirdly, it seems to me that the Goldilocks criteria means that surface planets are harder to create (more "complex"), which is also evidence that they represent a later form of evolution versus the more simple mechanism of ploons.
Finally, I won't deny that there's some element of wishful thinking that we humans are not some evolutionary dead end and evolution has designed us to survive and colonize the stars. If we are being replaced by ploons, that means that the evolutionary incentive is actually to kill us off as soon as possible to stop us from wasting available entropy.
Anyways, based on the above points, I think it's likely that ploons are actually the atavistic or backup method and surface dwellers like us are actually the current apex of cosmological evolution.
Thanks for the reply! I definitely agree with the broad strokes of your response. I don't have any particularly clever ideas, but I am curious about one thing:
If indeed we are throwbacks to an earlier evolutionary era, what other vestigial structures would be evidence towards that conclusion (other than our existence)?
I.e. part of your argument for the earlier phases is that even as evolution has moved away from immediate black holes as the primary reproductive mechanism, we still see black holes forming from dust clouds extremely fast. Ditto for star production and galaxies forming earlier than previously expected.
The sense I've gotten is that our solar system is weird (e.g. https://science.nasa.gov/solar-system/the-weirdest-solar-system-weve-found-so-far-you-may-be-in-it/), but maybe there are things to say in exoplanet development? Like the fact that there's a weird gap between super-earths and neptune sized planets?
Powerful stuff, Julian!
I suggest that there is a further line of thought indicated here: what are the necessary and sufficient conditions for the kind of life that can expand beyond its world of origin?
It seems to me that this requires the (probably rare) star-and-open-ocean origin (needs a catchy phrase for a name).
Life confined to water without a gaseous atmosphere won't develop mastery of fire or of electricity, at least in any scenario *I* can imagine. Without those, it won't develop mining, metallurgy, advanced tools, or spacecraft.
Also, how does such life further the evolution of the universe?
I am sure that many of us would welcome a future essay exploring this!
Best,
Jonathan
PS--If of interest, you might want to also explore the emergent DMT-verse; a domain in which PhD level researchers are now expressing confidence that there are repeatedly accessible dimensions with specific attributes. If correct, this would be yet another aspect of the evolving universe.
Hi Jonathan, thanks.
Good observations, and questions! I am extremely interested in this line of thought. I decided not to explore it in this post, because it was already too long. But I will definitely do so.
Yes, there are many limitations on underwater life. In fact John Smart (who has been very supportive of this project) has written about some of them. Here he is talking about that issue on Centauri Dreams, the forum for deep space news and ideas:
"So yes, many forms are possible, but only a few will be deeply accelerative, and thus dominate their environment, via competitive exclusion. Octopi could never reach our level even though they have two prehensile limbs and can build huts, because they can’t use tools and groups to dominate their environment. Water is too dense a medium relative to the force that can be generated by creatures made of protein. Cultural acceleration had to emerge first on land, etc."
Link to the whole thing: https://www.centauri-dreams.org/2021/12/31/the-goodness-of-the-universe/comment-page-1/
So how life in the liquid water oceans of icy moons might further the evolution of the universe becomes an interesting question, in the absence of technology. I do feel that we have an air/land chauvinism that might blind us to some of the possibilities down in those depths. I don't think technology is impossible. I do think it would have to develop down very different channels. It’s a rich, complex subject, where I would have to speculate far more than in this post (which is fairly factual), so I’ll do it in a separate post.
And of course, life on icy moons and life on exposed surfaces may have very different roles to play. Maybe we are the ones who do the going out, the exploring, the connecting, and icy moon civilisations are inward. Maybe we bring them our technology.
I don't know! I would just be speculating. It's an area where I would need to think things through from first principles, and even then reality is too rich for me to be confident of my guesses. But please feel free to point me towards anyone else exploring this area, it does interest me enormously.
As for DMT, that’s a whole other world that I have not really explored. Again, please do point me at anything I should read.
Julian, If there's anyone I know who can come up with a plausible way that a technosphere could emerge amongst aquatic life, it's you. I'll look forward to your speculations! (I'm still waiting for someone to develop your ideas for "fire breathing dragons" into actual experiments! That really should be incorporated into some quality SF storytelling.)
Were such icy moon-based intelligent life to focus on inward development, I should think that, given the presence of the same biochemical pathways for production of DMT found in all tested mammals and certain non-mammalian animal species and plants, it is entirely plausible that such life would have access to it, possibly with the capability to concentrate it and even to titrate dosages. (They might have far more sophisticated control of what we call autonomic processes than do we.)
Perhaps the most visible researcher is Danny Goler. Here's a recent interview he did; significant as much for what he doesn't say as for what he does: https://youtu.be/NJp2rASRKMc?feature=shared
If you wish to converse with Mr. Goler, I have a close friend who's been exploring the DMT-verse and who knows him personally. I expect that I could arrange an introduction.
Awesome post, Julian! Two thoughts/ questions about the Hill sphere and tidal forces...
1. The hill sphere for free planets is much larger than for captive planets, but are there other limits on how far out a moon can be and still experiencel forces from eccentricity enough to create oceans? I guess it depends on the eccentricity more than the distance... My thinking is just that the hill sphere isn't quite the whole story re how many ocean bearing ploons you'd expect to find. (I guess the gravity of the ploons themselves could also help hear each other up? But not much, I'd have thought)
2. If you have a ploon orbiting a binary stannet, presumably the double-tidal forces there are even more effective at generating heat than around a single stannet? On the other hand, forming stable ploon orbits seems likely to be much harder around double stannets. I guess it doesn't matter for the theory as a whole but I wonder if you think that binary stannets would be over represented or under represented as hosts of ocean bearing ploons.
(Written on my phone, sorry for phone artifacts)
Yeah, you are quite right William, the Hill sphere is only part of the story. The gravitational friction drops off with distance – but it rises with with eccentricity, so there are tradeoffs.
The orbit of a moon that is further out from its planet will experience less tidal heating than will one that is further in. Likewise, a moon with a less eccentric orbit will experience less tidal heating than a moon that's (on average) the same distance out, but in a more eccentric orbit.
So moons much further out might require more eccentricity in order to have liquid water oceans.
The limiting factor there then comes from the fact that resonances help stabilise the eccentricity of the orbit – which matters, because without it orbits can be normalised, and slowly become more circular over time. But stable resonances require low to moderate eccentricities. So if a moon is too far out, and needs an extreme eccentricity to generate enough gravitational friction / tidal forces to keep its subsurface water liquid, then it can't really get into and maintain resonance with other moons. Well, they can GET into resonances, but it's just more unstable. Highly eccentric moons can transfer too much energy to each other on a close approach, destabilise the whole arrangement, and one might even get ejected from the system.
Also, really extreme eccentricity can mean the orbits of two moons overlap, which can lead to serious near-miss disruptions, or even collisions.
So yeah, the Hill sphere may be waaaaaay larger around a stanet than it is around a planet, but the zone in which ploons can maintain liquid water oceans will be considerably smaller than the full Hill sphere.
As for binary stanets... My initial gut feeling is that it would be much harder for ploons to find and maintain stable eccentric orbits in resonance with each other in a binary stanet system. They would have to be pretty close to one of the stanets, in order to not be destabilised by the other stanet, which would kind of take away the large-Hill-sphere advantage of not orbiting a star. (Or they would have to orbit the common gravitational centre of the two stanets – their barycenter – which would mean orbiting waaaay out from both stanets. Which would make it hard to generate enough gravitational friction to keep the oceans liquid.)
Buuuuuut these binary stanets, these JuMBOs (Jupiter Mass Binary Objects), seem to be orbiting each other at a very large distance. Far larger than is usual for, say, low-mass binary stars (which tend to tuck in pretty close to each other). So both of the stanets in one of these JuMBOs could have pretty large Hill spheres. Then again, as the stanets making up these JuMBOs have much lower masses than even low mass stars, I don't know how stable that binary is going to be longterm, at such large separation. Pretty weak gravitational binding. Maybe most of those binaries will separate as they age.
Basically, great question, and I'll have to research this more deeply!
So good!
I’ve wondered about the potential of "rogue planets", but didn’t think the answer would be so exciting.
There’s also a throwaway sentence in there –
"evolving away far more slowly than us" – that gets to an aspect of time, that I have wondered whether shouldn’t be added to the Drake Equation.
Is it possible that life and intelligence on Earth developed at turbo speeds, relative to what would be "normal" in the universe? Life clearly needs some balance of change and stability to evolve. The deep oceans of a ploon sounds like an environment where the necessary kind of change happens very slowly. Is it possible, then, that thanks to the particular tilt and spin of earth, the orbits of earth and moon, etc. our planet has run through relatively quick and stable iterations of change necessary for the evolution of life significantly faster than other life-supporting bodies?
I quite obviously don’t know what I’m talking about here, but it seems like an under-appreciated variable, seeing as how relatively small differences in speed of evolution should allow a late-starting planet to catch up with and surpass other planets or ploons that have been around for billions of earth years longer.
Yeah, I think you are right. The way energy is pumped into the Earth's geosphere, and biosphere – strong, rapid day/night pulses of energy, nested inside much longer winter/summer pulses – should lead to much more rapid chemical development, and then evolutionary development, on Earth that you would get in a colder, darker, less dramatically pulsed environment such as the liquid water oceans of an icy moon. I think evolution just has to happen slower in those depths. (But I may be wrong! If it's an environment optimised by evolution for the development of life, it could be surprisingly rapid due to non-obvious fine-tuned factors.)
The exposed surfaces of rocky planets seem to be higher risk, with higher instability, but also higher speed of development.
We shall (eventually) find out...
"An advanced civilisation that developed in a single, vast, subsurface ocean, beneath a crust of ice twenty or fifty or a hundred miles thick, may never even conceptualise a larger universe – an elsewhere – let alone explore it."
I know this was not the point of the essay but this smacked me very hard in the face, and I can't stop thinking about how, if true, this could position humanity (or Earth life generally, or maybe rocky planet life very generally) as having special access to the cosmos. And therefore, potentially, from an animist perspective, a special role in the universe a la "we are the cosmos coming to know itself"
Could that be a trait worth conserving, despite the relative inefficiency of creating conditions for rocky surface planet life? Could "coming to know itself" help direct future universal evolution somehow? Is there a cultural exchange between rocky surface planet life and icy sea moon life that kicks off the third stage black holes, so both types are needed for max optimization?
I think you might well be right, Alaina. It's a weakness in the piece, that I didn't explore the idea that our access to space (as air-breathers on the exposed surface) might be a feature, not a bug. I've been talking about this to a few people, and the feeling is, that humans (and other rocky planet surface dwellers, in other stellar systems) seem positioned to go out there and connect things in a way that water-dwelling, deep ocean civilisations, that developed under a hundred miles of ice, just won't be able to. Or want to.
So yeah, there may well be an evolved role for creatures like us. We are specialists in directly knowing the larger universe, and joining the dots metaphorically and physically. Those asteroids and comets can't just burst into life on their own. They need someone like us to come along.
A creature that evolved under a hundred miles of water that's under another hundred miles of ice is just not going to find it as easy to do that, for all kinds of reasons.
So yeah, we may indeed have a special role in the universe. Good!
> But our theory argues that intelligent, technology-wielding life in a universe helps that universe reproduce. (See this for more details
That theory is that black holes result in the creation of new universes that "evolve" parameters slightly different from parent universes. There was no explanation as to how "intelligent, technology-wielding life" would result in more such black holes rather than being a side effect of a universe which happens to produce such black holes.
> So that’s number 1, liquid water oceans, and number 2, heat. Icy moons beat rocky planets on both counts. Much more water, much more efficiently heated.
An efficient usage of a much smaller amount of energy can still result in less warm water than an inefficient usage of a FAR larger amount of energy. You would need to do a calculation of how much energy is available for life on rocky planets vs icy moons rather than just labeling one "efficient" and leaving it there.
> intelligent lifeforms wield technologies to manufacture artificially small black holes (for maximally efficient energy production)
That's what's missing from your linked post. But why would intelligent life do that? Wouldn't it be simpler to create energy via fusion on scales too small to create a black hole? Black holes don't release light as energy, they seem strictly inferior from the perspective of life outside of them.
In your other post you mention that Darwin didn't know about DNA as the mechanism for transmitting information from parent to offspring. That may be true, but he could observe the similarity in phenotypes (Galton was to make much of it in humans, and animal/plant breeders had noticed it earlier). We can't observe any such similarity, as we only observe our own universe. Instead of a stylized fact in need of explanation, you've got both an imagined/unobserved "fact" and a lack of explanation.
Nice argument! A couple misstatements
Tidal heating of planetary moons is the energy of the moon slowly becoming less excentric.
The molten moon core is not heated by pressure but by any _increase_ in pressure if the outer layers of the moon are slowly collapsing toward the center; no movement no increase in pressure, no heating. [The core may also be molten from the initial heat of formation and may be heated by decay of radioactive elements.]
Intriguing post. I think where the evolutionary logic may breakdown is the idea we can do probabilities on infinities. David Deutsch talks about this in his book Beginnings of Infinity in the context of the multiverse. The question is whether universe generation is a finite process with some fixed number of universes possible (in which case we can make the anthropic argument that we are more likely to find ourselves in a evolved universe as you describe), or if the number of universes is infinite, in which case we cannot argue the anthropic case. This is because you cannot say one infinite number is larger than another infinite number, they are both infinite!
New Reader. Thanks Marginal Revolution. Wow! (I haven't finished yet.) First the 'poster' of the moons is great. (I'm going to limit my exclamation marks.) Second, we should send probes to all the water moons. Finding other life would be huge. Maybe ask Musk to help? (Keep cost down.) Third about the unexpected planet forming regions; Have you heard about MoND? And are the regions in the mond regime? (local gravitational acceleration less than 10^-10 m/s^2.) Probably not, but it's worth asking I think. And finally I find some of your ideas to be a bit crazy... which is fine and fun, I have some crazy ideas that I love, but I try and remember that my crazy ideas are probably not true. (Which does nothing to stop me thinking about them... but somehow keeps me grounded...?)
The conventional Goldilocks story has a bunch of requirements that limit life: rocky planet, liquid water temperature, cleanup of bombarding rocks, protective magnetic field, nutrient recycling by tectonic activity, etc, and (I expect) a bunch more that we haven't figured out yet. Some of these may be soft edged, like they permit the evolution of slime but not much more. There are some interesting chemical ideas on the origin of life, but nothing is established so we don't know what the physical limits are. We are more at the how-could-it-even-work stage, rather than any kind of a clear understanding of what can and can't happen.
I see a reasonable case for oceans on moons and ploons but whether (eg) DNA works at 20,000 atmospheres - or whether there is actually an alternative to DNA that does work - is as far as I know an open question. It's possible to go glass half full and say evolution over an astronomical number of natural experiments will find a way, but it's also possible that one or more hard limits will rule out life of any kind in these seas. There's a bunch of unknown unknowns and some may be a big NO.
The evolution of higher brainy life is another giant step that won't happen anywhere. There was about 2 billion years when of only algae on Earth and it might have gone no further but for the high productivity of sunlit coastal zones that made predation of grazers an option. There's an interesting argument that there's an upper limit to viable brain development in the sea. Visibility is a matter of metres so there's not a lot of value in planning. You sit on a rock or at best swim around hoping to bump into something that you are able to eat rather than something that eats you. The smartest creatures in the sea evolved on land.
Oh, Re: Living in the ocean, you develop hearing and sonar.
> or whether there is actually an alternative to DNA that does work
Isaac Asimov pondered different chemistries at different temperatures: http://www.bigear.org/CSMO/HTML/CS09/cs09p05.htm but from what I've heard, scientists since then don't think his other possibilities are viable.