Holy crap, I've just realised that cosmological natural selection gives you the structure of the universe (FIRST DRAFT #1, give me feedback...)
OK, I’ve got a brilliant idea, not yet well expressed. (I tweeted it to a grumpy old man.) Help me make it better.
In a minute, I’m going to blushingly show you the – extremely raw – first draft of what I think will be an absolutely crucial chapter in the book, and then ask for your comments and feedback. But first I’d better explain where this first draft came from. (This is all part of revealing the process of writing the book, which will interest some of you more than others. No problem; bail if this isn’t your thing, or just skip to the draft itself, below. Or go read a different, more finished, part of the book, like this introduction.)
BACKGROUND:
I recently (to my great surprise and delight!) realised that the evolved universe theory that I am developing here automatically generates the extremely peculiar structure of our universe. That is, Darwinian evolution at the level of universes can explain why the vast majority of our specific universe is hostile to life, while small islands of chemical complexity (like Earth) are extremely hospitable to life. It’s not random, and it’s not inexplicable: it’s a logical consequence of evolution at the level of universes, if universes reproduce, with slight variation and inheritance, through black holes giving birth to big bangs. (The form of reproduction Lee Smolin argues for in his theory of cosmological natural selection, which my evolved universe theory builds on.)
This is, to put it mildly, a hell of breakthrough for the book, and I have been wandering around in a warm glow, like a guy in a Ready Brek ad, ever since.
The realisation came while I was browsing what I still think of as Twitter (though Elon Musk has changed so many features – including allowing edits, extremely long tweets, and peeing in other people’s pockets for eight bucks – that it is no longer really Twitter, it’s an entirely new platform; so yeah, I should probably call it X now).
One of the cosmologists I follow there is Will Kinney, Professor of Physics at the University at Buffalo (State University of New York). He specialises in the structure and origin of the universe, he’s the author of An Infinity of Worlds: Cosmic Inflation and the Beginning of the Universe, and he really knows his stuff. (I mean, I think he’s wrong about a bunch of that stuff, because I think everybody is wrong about that stuff, but he is totally on top of the current reductionist materialist mainstream model of the universe.) He’s also an extremely grumpy old man (or enjoys pretending to be an extremely grumpy old man; it’s certainly a fun persona that works well on Twitter, sorry, X). Will never engages with me (he probably, and perfectly understandably given his background, thinks I’m a nut), but I still like trying to engage with him, partly because he asks such interesting questions. (He’s not interested in your answers, unless you are another grumpy old man, because he is, well, a grumpy old man, but the questions are great.)
And recently he tweeted this:
Which is a terrific tweet, worth unpacking. For those of you unfamiliar with the Anthropic Principle, let’s just raid Wikipedia:
The anthropic principle, also known as the "observation selection effect", is the hypothesis, first proposed in 1957 by Robert Dicke, that the range of possible observations that could be made about the universe is limited by the fact that observations could happen only in a universe capable of developing intelligent life. Proponents of the anthropic principle argue that it explains why the universe has the age and the fundamental physical constants necessary to accommodate conscious life, since if either had been different, no one would have been around to make observations. Anthropic reasoning is often used to deal with the idea that the universe seems to be finely tuned for the existence of life.
The anthropic principle has always been a fairly half-arsed and philosophically naive attempt to explain why our universe contains orderly and highly complex living things, for many reasons, which I will address more fully in another post. (Lee Smolin and the distinguished father of string theory Leonard Susskind had a ding-dong online battle about the anthropic principle back in 2004, which is well worth a read.) Anyway, there are a bunch of versions of the anthropic principle, and, as the philosopher Nick Bostrom has dryly pointed out,
Many 'anthropic principles' are simply confused.
But Kinney’s tweet gets to the heart of an interesting problem that most versions of the principle overlook.
Why is so much of this universe – the vast majority of it, in terms of volume, in terms of mass – so outrageously hostile to life… while Earth, this tiny island afloat in the void, is extremely hospitable to life?
THE USUAL STERILE DEBATE ABOUT LIFE
The usual debate about what life in the universe tells us about the universe is totally sterile. Some people point at the vast expanse of void dotted with occasional black holes and nuclear infernos (ignoring Earth as an irrelevant, rare, random, and probably accidental rounding error), and say, “See? The universe is utterly indifferent to life!” Others point at the profound richness of life on Earth (ignoring the vast surrounding expanse of void dotted with occasional black holes and nuclear infernos) and say “See? The universe is built for life!”
But both are true. What is more interesting is to explore, why both?
Look at it again: Life is simultaneously marginal in this universe (99.99999999999999% of it cannot support life), and yet in that remaining 0.00000000000001% it is highly supported. Odd combination.
And, pondering this, inspired by Will’s tweet, I came up with an actual explanation.
So I wrote a long answer to Will (it took me several days, and several drafts – I was working out my ideas as I wrote), and posted it on Twitter, sorry, X, in reply to his tweet.
Of course, he probably didn’t read it. I do not blame him: the obvious reaction, on Elon Musk’s brave new X, to someone posting several thousand words in reply to a casual tweet from a week earlier is to assume they are a lunatic, because 99.999% of the time, that will be true.
But I think I actually answered his implicit question – and if I DID, then I have explained the structure of the universe. And even given a mechanism for delivering it. Which is a hell of a thing, if true. And it seems a shame to just leave that as a neglected week-late answer to an obscure tweet, buried unread in the inbox of a grumpy old man.
Now, I do intend to convert this mega-tweet into a chapter in the book… but that could take a loooong time. One problem with this tweet is that I was writing it directly to an excellent physicist and cosmologist, so I didn’t really need to explain technical terms, and could assume a huge amount of background knowledge. For the book version – for a general readership – I will have to rework the mega-tweet heavily, and give a lot of background.
However, I am eager to put the idea in front of you now, while it is fresh.
GIVE ME FEEDBACK OR GIVE ME DEATH
And I am PARTICULARLY eager to get feedback on it now, right at the start, so that I can improve the eventual chapter.
So I’m pasting the original tweet in below, raw, even though it’s going to be dense and often impenetrable to anyone with no physics background. (I did briefly explain a few concepts, and answer a couple of obvious questions, because I was aware that, as an open reply on Twitter/X, people other than Will might read it, and I wanted to help them follow it; but in general it’s dense, and everything is under-explained.)
However, I would greatly appreciate you reading it anyway, if you can! That would help me hugely in writing the chapter. Tell me what you need explained. Tell me where the logic isn’t clear. Tell me where you think I’m wrong. (And also, on the positive side, please do tell me which points, or analogies, or lines, stand out, or are particularly clear or useful or exciting, or make you go “Ah!” That helps a lot, too. ) And of course, if you DO have a physics background (or an evolutionary biology background), your critique, both negative and positive, would be even more useful. In fact, if you have a friend who is a physicist/astrophysicist/cosmologist/evolutionary biologist (or a student in one of those fields) – I would love you to pass this on to them, and ask them to give feedback. Basically, all feedback, whether on style or content, whether from a position of knowledge or ignorance, is helpful and welcome.
(If this experiment works, I may post other early drafts to similarly solicit feedback; I’ve therefore titled this First Draft #1, to help people find, or avoid, such posts, according to taste.)
So, here’s Will’s tweet again, in case you’ve forgotten:
WILL KINNEY’S TWEET
“One of the reasons I don't believe in the Anthropic Principle is, that almost all of the universe is savagely deadly to warm little meatbags like us.”
And here is my epic reply, explaining the structure of the universe in evolutionary terms, cut ’n’ pasted directly from Twitter, sorry, X. (I’ve added some headings, to help you navigate it, and embedded some links, to give you quick access to background information.)
MY REPLY
Agreed. The anthropic principle is balls. The enjoyably provocative way you phrased it, though, got me pondering, and I think I’ve come up with an interesting hypothesis. (It took me a few days, thus the delayed reply.) Curb your natural desire to snort derisively and stop reading at the first line you disagree with, and read to the end; it comes together, I think. And then – but obviously only if you have time, and believe the argument is worth engaging with – give me a couple of lines of feedback. I’d be interested in your critique. (I’m writing a book on this, so feedback from subject experts is extremely valuable.)
OK. There are two important, entwined questions about our universe that can be extracted from your comment. One is, why is 99.999999999999% of it so incredibly hostile to life? (Or maybe better to say, absolutely and ferociously indifferent to life.) And the other question is, why is 0.0000000000001% of our universe so incredibly hospitable to life? A vast, inhospitable universe that is mostly hydrogen and helium plasma in a vacuum, yet which contains small, hyper-complex sub-regions which use all of the dozens of naturally stable elements to build rich solid/liquid/gas environments hospitable to “warm meatbags” is a deeply peculiar structure.
An evolved universe theory (one that expands and improves on Smolin’s old idea of cosmological natural selection) not only gives you an answer to both of these questions, it also shows you that such a peculiar-looking structure is the most likely result of an evolutionary process. (Stop rolling your eyes and hang in there, Will. We are going somewhere interesting.)
Essentially, you can see the evolutionary history of universes in that structure. An evolved universe – as the generations pass, and (along our successful evolutionary line) each new universe grows, on average, more complex and reproductively successful – nonetheless has to conserve many of the attributes that made its primitive ancestors successful. It has to build on that; it can’t just throw it away. (Just as mammals today, though wandering around on dry land, are still essentially membranes full of salty water – and indeed start their development inside a bag of salty water, inside their mother – because the earliest life evolved in the sea.)
WHAT DID A PRIMITIVE, EARLY UNIVERSE LOOK LIKE?
So, what did a primitive early universe in our direct evolutionary line look like? The one thing we know about it is that it reproduced successfully. And it probably didn’t do much else. (The DNA analogy is with early prokaryotic bacteria.) So the earliest universes were essentially simple black hole/big bang/black hole/big bang sequences, with some universes producing more black holes, and thus more big bangs, and thus more offspring, than others.
That is, with primitive universes, after the Big Bang that gave birth to them you pretty much immediately got a small number of direct collapse ultramassive black holes, or (in the more reproductively successful universes) many direct collapse supermassive black holes.
Bear in mind, given that evolution at the level of universes occurs through slight variations in the basic parameters of matter (and that this is an era long before the evolution of our current highly advanced fine-tuning of those basic parameters), matter itself is pretty primitive at this stage; we don’t have the hyper-evolved, ultra-complex, extremely stable, homeostatic, dynamic, out-of-equilibrium contemporary proton, for instance. But such complexity isn’t required yet; all that such ur-matter needs to do is expand, break up into more than one piece due to that expansion, and collapse.
(A note for any non-physicists reading this over Will’s shoulder: that means each of these primitive supermassive or ultramassive black holes, with a mass equivalent to hundreds of thousands, or millions, or even billions of suns, formed directly from the collapse of a single smooth cloud of gas, without the cloud breaking up into denser subregions and forming stars as it collapsed. In our specific universe today, there’s a supermassive black hole at the centre of pretty much every galaxy, but most black holes are much smaller, and are formed, in a more complex process, by the collapse of a star once it has burned all its fuel. Those smaller, stellar mass black holes – there are countless millions per galaxy – massively outnumber the supermassive black holes – of which there’s roughly one per galaxy.)
So, direct collapse ultramassive or supermassive black holes are conserved from the earliest, most primitive universes. They are fundamental to all universes in our evolutionary line. And those universes would have randomly explored that evolutionary possibility space for many, many, many generations, with primitive universes that produced greater and greater numbers of direct collapse supermassive black holes coming to dominate the total number of existing universes. (Another note for any non-physicists reading this over Will’s shoulder: Given that mass energy and gravitational energy net out to zero in our universe – as do positive and negative electrical charge, etc – there is no practical limit to the number of offspring universes this evolutionary line can have. You can make a universe from essentially nothing. Child universes don’t get smaller and smaller.)
WHAT IS THE NEXT MAJOR EVOLUTIONARY BREAKTHROUGH, ALONG OUR UNIVERSE’S EVOLUTIONARY LINE?
The next major evolutionary transition for universes in our evolutionary line comes when, eventually, in some universe, a random slight variation in the basic parameters of matter leads to each of those supermassive black holes having some leftover, ragged, fragmented, uncollapsed material orbiting them. When these smaller fragments do start to collapse, they’re not massive enough to just keep on collapsing to form direct collapse black holes, but instead get stuck halfway, and form large numbers of proto-stars. (Note for non-physicists: as the collapsing nuclei are driven closer and closer together under the influence of gravity, they begin to fuse, releasing energy as radiation, until that radiation is enough to balance and thus pause the gravitational collapse – so you get a stable star.) Those proto-stars eventually run out of fuel and collapse further to make large numbers of stellar mass black holes.
This is a huge breakthrough in reproductive success; it’s a mutation that soon comes to dominate the overall number of universes, as it produces far more offspring than a purely direct-collapse-supermassive-black-hole universe. The hugely increased number of offspring can then explore the possibility space for the particular fine-tuning of the basic parameters of matter that has generated them. That process is refined further by evolution over time until supermassive black holes actively generate highly efficient star-producing galaxies, optimising the translation of matter into black holes.
Incidentally, I predicted this model before the James Webb Space Telescope released its first data, and everything it has seen since backs my model: the remarkably (but not perfectly) smooth early universe, immediately post Big Bang, is optimised by evolution for direct collapse supermassive black hole production (not star production), and it’s the supermassive black holes which then optimise conditions in our universe for rapid star production. (By attracting, enriching, and shocking the remaining gas, while removing its angular momentum, by way of the accretion disc and jets.) So the mass-balance between supermassive black holes and stars in early galaxies should be tilted heavily towards supermassive black holes. Which is exactly what we are seeing. And galaxy formation should be rapid, efficient, and early. (Not slow and bottom-up.) Which is exactly what we are seeing.
Anyway, that’s the largely hostile-to-life, hydrogen-and-helium-in-a-vacuum universe. That’s where it came from, in evolutionary terms. It’s incredibly hot-and-high-pressure (stars) or incredibly cold-and-low-pressure (space); and that’s it. It’s not deliberately hostile to life; there is no life yet to be hostile to. It’s simply indifferent to life’s potential future needs. But it is tremendously reproductively successful: it generates a lot of black holes, and thus big bangs and thus child universes. And it has infinite time, and as many generations as it wants (with a lot of offspring in each generation), to explore the possibility space for those basic parameters of matter. (If it’s exploring that possibility space in a random walk, then many of its offspring will of course be LESS evolutionarily successful, or not successful at all; that’s fine, we are not descended from those dead ends. I’m just concerned with exploring our direct evolutionary line, the one that leads to this universe.)
WHY DO UNIVERSES ALONG THIS EVOLUTIONARY LINE EVENTUALLY GENERATE LIFE?
Now I’m going to explain why such a universe ultimately generates life of the kind we see on earth – and in particular, how generating things like human beings can be a reproductively successful strategy at the level of universes. This is where I’m going to lose a lot of people, probably including you, Will, because it will feel speculative, science fictional. Fine, I get your reluctance, but hang in there to the end, the argument is much, much stronger than it looks at first glance. (Even Smolin hates this step, bless him, but he is wrong; he hasn’t fully thought it through, because he doesn’t know enough about evolution.)
OK, eventually, at some point, a typical somewhat-evolved universe, comprising a few direct collapse supermassive black holes plus many more stellar mass black holes, makes the next revolutionary breakthrough, or step change; it generates matter that can copy itself – maintaining and iterating an orderly structure over time – and that can manipulate other matter. Let’s call it life, to separate it out a little and allow us to discuss it, although it’s still just increasingly fine-tuned matter obeying increasingly fine-tuned physical laws. (No humans or human-like things yet in these early life-exploring universes.) Matter that can manipulate matter, and that can copy itself – life – grows more complex, generation of universe by generation of universe, as those universes generate more elements – as they blindly explore the possibility space opened up by stars, and thus fusion, and thus stellar nucleosynthesis. Note that so far this life-matter isn’t a new breakthrough, this is just the slow arbitrary complexification that comes with any evolutionary mechanism. (An example from DNA evolution: the plumage of the birdlife in Borneo complexifies over time, even in the absence of new threats or environmental changes.)
((Later note from me, not in tweet: this is a bad example, as sexual selection, rather than natural selection, drives such plumage change, and there is no equivalent to sexual selection for universes. I should have thought a bit deeper, and come up with a purer example of random genetic drift, where sexual selection wasn’t a factor. Anyway, as you can see, I have managed to grit my teeth, restrain my perfectionist urge, and put up this draft faults and all. And yes, I’ll fix this in the finished chapter. End of note.))
But at some point – remember, this has been happening forever, we have infinite time, an infinite number of generations of universe are possible – the matter that manipulates matter – life – gets complicated enough to control its source of energy. And once it can control that, it will control that, because life inside a universe needs to take energy from that universe in order to maintain its out-of-equilibrium orderly structure. Another way to think of this is that a universe is both organism and environment – energy-user and energy-source – which is why so much of our own specific universe ends up devoted to efficient long-term energy production (through very slow, stable fusion processes in stars).
CHASING ENERGY UP THE EFFICIENCY SLOPE
And so life chases energy up the efficiency slope, starting with chemical processes (converting pretty close to 0.0% of the fuel’s mass to energy). Our own sequence has been: our muscles, then animals’ muscles, then wood, wind, coal, oil, gas, solar… As life grows more complex – or put another way, as matter gets better at manipulating matter, by manipulating matter into forms that could not be generated by nature, but which can manipulate matter better than natural forms of matter can, at both larger and smaller scales, ie technology – it unlocks more efficient processes. Fission (converting 0.1% mass to energy) is way more efficient than chemistry; fusion (0.7%) is even more efficient than fission; but black holes (up to 42%) convert more mass into energy than anything else, even fusion. So the logic of life is that it will try to make very small black holes; they are the most efficient energy source, in our evolutionary line of universes, and so any self-replicating lifeforms that require energy to survive will converge on that solution.
Can life make small artificial black holes? Sure, given enough time. As David Deutsch has pointed out, anything that isn’t ruled out by physical laws is possible. And technological evolution, partly because it is directed by conscious agents, vastly outstrips DNA evolution in speed (which, in turn, vastly outstrips the speed of evolution at the level of universes). Technology is just matter manipulating matter to manipulate matter even more efficiently. And once that process starts, progress is exponential. As we can see from our own recent history, life gets really good at the second-order manipulation of matter by matter – technology – really fast.
((Later note, not in tweet: The mathematician Louis Crane has written a couple of papers on the optimum size for artificially-made energy-producing black holes, and possible methods for making them. I should have mentioned those papers here – Will would probably have liked a link to an actual peer-reviewed paper exploring this, rather than my handwaving – but hey, it’s a flawed first draft.))
And once lifeforms inside universes, as subunits of those universes, are able to generate, through technological means, small, efficient, black holes for energy production, then you’ve had a third major evolutionarily breakthrough, into reproductive hyper-success. Descendants of such a universe will vastly outnumber the descendants of simpler few-supermassive-black-hole/many-stellar-mass-black-hole-producing universes. And so, the evolutionary possibility space of this new kind of universe, which produces not just supermassive black holes and stellar mass black holes, but also vast numbers of much smaller, artificially produced black holes (with life, and its needs, as the mechanism of production), will be explored very, very thoroughly. Our universe is part of that phase of evolutionary exploration.
WHAT IS THE MATTER WITH ANTIMATTER? AN ASIDE, GIVING AN EVOLUTIONARY EXPLANATION FOR THE LACK OF SIGNIFICANT QUANTITIES OF ANTIMATTER IN OUR UNIVERSE
Interesting side note: Matter/antimatter annihilation (100% conversion of mass to energy) would be even more efficient than small black hole production; but no evolutionary advantage would accrue to a universe in which life skipped past small black hole production to matter/antimatter annihilation. So any universe containing a great deal of matter AND antimatter should be far less reproductively successful than one containing only one or the other. (Likewise for universes where antimatter was easy to produce.) And sure enough, our universe does not leave any significant quantities of free antimatter floating around. (Sure, you can make some antimatter, but making antimatter, in the real world – thanks to fundamental, and thus unavoidable, practical problems like bremsstrahlung radiation and the exclusion principle and blah blah blah – always takes more energy than you could ever get back.) In other words, the extreme matter/antimatter imbalance in our universe is something that mainstream cosmology has a lot of trouble explaining – but it would be an obvious direct consequence of this model of cosmological evolution…
Anyway, after many, many generations, with evolution blindly fine-tuning the basic parameters of matter in each generation, the reproductively dominant universes will briskly and efficiently use their supermassive black holes to produce galaxies of stars (and thus, ultimately, stellar mass black holes): will briskly and efficiently produce planets suitable for life around those stars; and will briskly and efficiently produce the conditions for life on those planets.
AN EVOLVED CHEMICAL LOGIC QUICKLY PLAYS OUT
There is an evolved chemical logic which plays out here at this point, complexifying the geosphere from, say, the initial dozen or so minerals found in the cloud of gas and dust from which our earth formed, to a couple of thousand minerals by the time life started, to the five-and-a-half thousand minerals Earth has now, as a fully-fledged, self-regulating biosphere. (See Robert Hazen et al, Mineral Evolution. Or Hazen’s new paper, led by Michael L. Wong, out this week in PNAS: On the roles of function and selection in evolving systems.)
Once the geosphere has complexified to the point that a biosphere can now commence (a purely chemical process, which has by now been refined by evolution, at the level of universes, to be quite brisk in any specific universe along this evolutionary line, such as ours), life then has to self-assemble upward into complexity on these planets, which, unavoidably, takes quite a while – complex multicellular organisms can’t just simply come into being on any given planet inside any given individual universe; they have to be ratcheted up into that complexity over billions of replication cycles under intense evolutionary pressure, customising life to the conditions on that particular planet. But once sufficiently complex life has self-assembled, it will briskly and efficiently produce large numbers of small, artificial black holes. And all of this will play out directly from the extreme, evolved, fine-tuning of the basic parameters of matter.
By the way, when I say “efficiently”, right up until that last (technological) step I mean the kind of efficiency you get from a blind evolutionary process, not a directed technological process. As my biologist friends point out to me, evolution isn’t particularly efficient – it’s gloriously wasteful and sloppy – but it nonetheless gets the job done. So the evolved efficiency of our universe resembles the evolved efficiency of, say, an oak tree, producing several million grains of pollen and tens of thousands of acorns per year. Less efficient than the dream of perfect efficiency a technocrat could imagine; infinitely more efficient than randomness.
HURRAY FOR THE WARM MEATBAGS, UNEXPECTED HEROES OF COSMOLOGICAL NATURAL SELECTION!
As you can see, a vast inhospitable universe of hot plasma and cold void (dominated by supermassive black holes, each of which is surrounded by a huge number of far less massive stars which generate huge quantities of stellar mass black holes), which nonetheless, briskly and efficiently, generates extremely small, well-protected temperate zones for hyper-complex life (capable of, at some point, generating incalculable numbers of tiny, energy-efficient, black holes), is a logical outcome, under an evolved universe hypothesis. The warm meatbags, funnily enough, are the most reproductively successful part of the universe. So they are extremely strongly selected for; you should find them, or at least matter-manipulating-matter that functionally resembles them (the meatbags may be a transitional stage to something that would look, to our eyes, more technological), all over this universe; you should find them all over many, many, many, many, many other universes.
But the plasma and the inhospitable void are conserved, because you can’t get to the warm meatbags without them. And likewise the meatbags are conserved (even though a warm meatbag may well be inferior, from the universe’s point of view, to a far more skilful technological/AI entity that can more efficiently bang out small black holes) because you can’t get to the technological/AI entities without generating the meatbags first.
Note the complexification of everything, at every level, here. In earlier, more primitive universes, primitive proto-matter would’ve just directly collapsed. Now it’s highly evolved hydrogen doing the job, but it doesn’t need to be. That is, deep in the evolutionary past of universes, direct collapse supermassive black holes would not have even needed elements. Big Bangs, black holes, Big Bangs, black holes; each new generation was just the expansion and collapse of a primitive protomatter.
UNIVERSES EVOLVED. WHICH MEANS MATTER EVOLVED. WHICH MEANS EVOLUTION EVOLVED.
But – given that the basic parameters of matter can vary slightly in each generation – matter itself has evolved. And, nested within that, generated by that matter and the increasingly complex evolved chemistry of increasingly complex evolved fermions and bosons, DNA evolution has evolved.
Evolution evolved. This, incidentally, answers another of your questions (I think you asked this last year):
“The fact that the age of the Earth and the age of the universe are even remotely similar numbers is honestly pretty weird. Why isn't the universe a trillion times older than the solar system?”
(Yeah, I just went and checked; you tweeted that on Dec 17th 2022.)
If there were just one universe, and if that universe were made of matter with arbitrary characteristics just moving around blindly at random, sure, it would be weird. But by this point in the evolutionary history of universes, an evolved universe is going to build out worlds, and life, rapidly and efficiently. The fact that the age of the universe and the age of the Earth are so close is extremely strong evidence for the theory. And of course your intuition is valid; our universe must have descended from earlier, less efficient universes, where it DID take far, far longer to build out habitable worlds, and life. But the looooong evolutionary process that sped up and optimised that developmental process, all happened at the level of universes, across many generations of our ancestral universes. Not inside the lifetime of this one.
Right now, in this particular universe of ours, countless generations later, elements are complex structures of protons, neutrons and electrons – with the protons and neutrons themselves, in turn, extraordinarily complex, having by now been fine-tuned by evolution to generate this complex, reproductively successful universe.
LIFE AT A LOCAL FITNESS PEAK
In evolutionary terms, we are, by now, at an extreme local fitness peak. (Which is expressed as extreme fine tuning, by a blind evolutionary process, of the basic parameters of matter.) Tweak any of those basic parameters by much, and you don’t even get solid matter, let alone galaxies, let alone life, let alone humans building space telescopes. Put another way, it would be hard, at this point, to jump to a very different (but equally reproductively successful) form of universe from here. We’re like a giraffe, or a humming bird. (Or an amoeba: who knows how complex universes can get, and have got? We are just at the end of one evolutionary line. There are, no doubt, many others.)
And if you look at the basic parameters of matter in our universe, they are of exactly the kind you would expect after a long evolutionary process has fine-tuned them. That is, they are all over the fucking place. What has been fine-tuned is, essentially, their relationships to each other, which have been adjusted, and adjusted, and adjusted by countless generations of evolution, to generate this kind of ultra-complex universe: the kind with things like us in it. The fine structure constant, the mass of the electron, the precise parameters of the strong nuclear force… their values are what they need to be in order to produce this reproductively successful universe.
This leads to lots of weird-looking fine-tuned relationships between parameters that generate highly unlikely-looking consequences, that happen to be extremely functional in terms of that reproductive success. Note how, say, the strong nuclear force becomes repulsive at a certain density of matter; thus, large collapsing stars can, while also making a black hole (early form of reproductive success! Conserved!), go supernova, and thus distribute the heavy elements required for planetary formation back out into the interstellar medium where they are needed (for later-evolved, more efficient forms of reproductive success!) – even though those elements were manufactured at the bottom of an incredibly deep gravity well.
Superficially, that resembles the anthropic principle; actually, it’s completely different. An evolved universe theory doesn’t postulate an infinite number of random universes; it postulates a large but finite number of universes, and gives you an explanation, and a mechanism, for generating each one, from an absolutely primal original simplicity.
Bonus feature: no arbitrary creation-out-of-nothing is required: there was always something, and it was probably incredibly, ridiculously simple for a ludicrously long time. We have, however, clearly now hit the hockey-stick inflection point on the complexification graph… But, as the NUMBER of universes shoots up, along with the complexification, then there is no Baysian unlikelihood problem. Most universes, at this point, are likely to be complex, because the most complex ones are the most reproductively successful ones. And so we human beings are in an extremely common kind of universe, not an astonishingly rare one. (A VAST improvement on the anthropic principle.)
THERE IS NO HIDDEN SYMMETRY
This has another consequence: everybody looking for a simple underlying law, or for any kind of mathematical elegance underlying the weird, arbitrary-seeming numbers that comprise the basic parameters of matter in our particular universe – through supersymmetry, and so on – is doomed to brutal disappointment. There is no hidden symmetry. No hidden mathematical elegance. The elegance is in the universe itself. Not in the pragmatic, messy, evolved parameters that generate it.
(One of, er two. Wow, I broke X.)
((Later note, written after the tweet: Yeah, at this point I had managed to max out X’s new epic tweet length. Oy. So, this is the end of the first tweet and the beginning of the, much shorter, second; I’ve left the original notes I wrote at the break-point, above and below, for flavour.))
Where were we? Oh yes. Second of two. (Don't worry, we're nearly done.)
A JAGUAR IS ELEGANT
Similarly, a jaguar is elegant; its DNA (packed with the necessary fudges and compromises of a long evolutionary history) is not.
Such fudges and compromises are inevitably present in the basic parameters of matter, because, as universes grow more complex over the generations, earlier aspects nonetheless have to be conserved. You can see this play out in the developmental unfolding of our universe after the Big Bang: the interactions between the basic parameters of matter generate unlikely yet functional glitches, that would be very hard to explain in a one-shot universe, but which make perfect sense in an evolved one.
The flipping of the strong nuclear force during stellar collapse is one; another nice example is the deuterium bottleneck. If the basic parameters of matter in our universe allowed stable isotopes with an atomic mass of 5 or 8, then everything would fuse at the temperatures and pressures found straight after the Big Bang, and you wouldn’t get the nicely balanced initial hydrogen-and-helium mix that allows for the step-by-step developmental unfolding of stars and planets and life – and thus this complex, highly reproductively successful universe.
DON’T MUTATE THAT MUTATION!
So, it’s very UNLIKELY, in a random one-shot universe, that you would get two islands of instability, at 5 and 8, and then none again until you get close to a hundred. But it is a very likely result, under an evolved universe theory, because it is a highly functional mutation which leads to extreme reproductive success. That is, if the basic parameters of matter simply vary slightly each time, and explore the possibility space randomly, that mutation, once it is hit upon, will be highly selected for: universes with that mutation will vastly outproduce universes without it. (But now they are constrained to preserve it; further mutations that lose that mutation will not reproductively prosper.)
How do you get, then, from a simple hydrogen and helium (and a bit of lithium) universe to one with many dozens of stable elements, and thus planets, and life? Well, step by step, mutation by mutation, breakthrough by breakthrough, through a random walk.
Carbon and oxygen would be a later evolutionary breakthrough that, at first, simply helped with more efficient star formation. You can make much smaller stars (and thus generate more stars from the same starting materials, and thus more stellar mass black holes, and thus more reproductive success) with some carbon and oxygen mixed into your hydrogen and helium. They act as coolants in the gas cloud, they help drive the triple alpha process in the core, and so on. (One of these things probably came before the other, but by now, tweaked by evolution, they do both really well.)
Complex biospheres of the sort we inhabit need a far more complex collection of elements; but you can see – just looking around our own universe – how the carbon and oxygen that helped make stars more efficient – and thus stellar mass black hole production more efficient – were conserved, and became the basis for organic chemistry and life.
This kind of repurposing of an evolved mechanism to fit a new, more complex purpose is very common in DNA evolution, where it is known as exaptation (i.e. feathers developed as insulation for dinosaurs get re-purposed, in later generations, as feathers that help their descendants, birds, to fly). So, even though we have an N of one, and can’t see any of the earlier more primitive universes that lead to ours, we can nonetheless trace the evolutionarily history of our universe through the increasing complexification of the processes (and the very elements) which generate supermassive black holes, stellar mass black holes, and technologically-produced black holes.
Nice, huh? An evolutionary explanation for the deeply peculiar structure of our universe.
Your thoughts?
((Aaaaaand… that’s the end of the original mega-tweet. Thank you for reading this far, and please put your feedback below. Any thoughts at all, that might help me make this clearer to the general reader, are welcome! And also: what do you think?))
Julian, I love your work and I found this essay endlessly fascinating. Before I say anything else, I must preface my commentary with the fact that I am not a physicist. Every corner of your essay you preceded with "Note for non-physicists", I smiled and waved. So from a physicists perspective, I may as well solely be a helpless meatbag to you. Perhaps like Will ignoring your long and delayed responses to his tweet (or to his X? what do we even call them now?), you too will ignore me and I will call you not an old grumpy man but a grumpy egghead. Jokes aside, I cannot provide commentary on your theory, so I hope I can provide feedback in the only other way I know possible and helpful. I pulled your content into a google doc and started going to work, giving feedback where I felt it would be helpful. I am through 5 of 16 pages so give me a few more hours or a few more days. My hope is that, should you decide to take snippets of this and turn it into a chapter in your book, that this feedback is any way shape or form, even in the slightest bit, helpful to you.
It is a pleasure reading your work and I admire your request for public feedback. https://docs.google.com/document/d/1wHiy37kXcrOmi28fSzRj29xOsEE9XOCNzQvCbh4q2zo/edit?usp=sharing
Are you familiar with Robin Hanson's work thinking through the implications of the existence of aliens? https://www.overcomingbias.com/p/explaining-all-the-weird-ufo-aliens
Since your theory suggests that our universe is tuned to give rise to sentient life with the capacity to manufacture black holes, it heightens the mystery of why we don't see more evidence for them through our telescopes. Hanson does some impressive math to show what this implies. He's a very rigorous thinker unafraid to come to unpopular conclusions - I think you'd like him if not already acquainted.
Keep up the good work!