JulianPGough

In a crude way, you could say so. Certainly, looked at through a purely evolutionary lens, the meaning of life for universes is (in one respect) to make as many black holes as possible. That maximises reproductive success for the unit of selection that is the universe. But of course, once consciousness enters the picture, things get more complicated. If conscious beings are generating most of the black holes in a universe for energy production (that are, as a side effect, generating child universes elsewhere, outside that parent universe), then the intelligent lifeforms making those black holes are going to feel some moral obligation to the child universes they're generating at the other side of those black holes. And if they have any control over the basic parameters of matter in the child universes, then perhaps they optimise for universes of a particular kind. They might not go for sheer numbers of offspring in the child universes. They might instead try to minimise unnecessary suffering in the child universe. They might not want the universes to generate life at all, because that's quite a moral weight to bear. Or they might want them to be maximally life producing, because life is intrinsically a good thing, from their point of view. It could go a number of ways. But it would certainly be true that a blind evolutionary search of the possibility space, in order to maximise black hole production, is no longer the case.

(Whoops, I was replying to "Why does there need to be an original?"; not sure why the reply ended up elsewhere.)

Yes! Fascinating, that you can only get stable planetary systems in universes with three spatial dimensions. More, and it all goes to hell.

Yes, this is a very common, and understandable, question; I get asked it a lot. But in fact new (child) universes aren't constrained in size by the initial energy/mass entering the parent black hole. Actually, that's one of the most attractive aspects of the theory. Universes have a huge reproductive advantage over, say, animals.

We know that in our own universe, the (positive) mass energy of matter and its (negative) gravitational energy net out to zero. But that means the amount of energy required to build a universe like ours is essentially… well, none. (See Laurence Krauss’s book, A Universe from Nothing; or Stephen Hawking and James Hartle’s 1983 paper, The Wave Function of the Universe, and Hawking’s later book with Leonard Mlodinow, The Grand Design, etc.)

Child universes are therefore effectively free to produce. Thus, over time, evolution will favor making more (and smaller) black holes from the same amount of matter. Yes, the black holes will get smaller – but the universes they give birth to, through Big Bangs, will still be full sized.

And universes aren’t constrained by a shared environment with limited resources – newborn universes aren’t all competing in a valley with a limited amount of grass. Indeed, each new universe is entirely self-contained and self-sufficient, being both organism and environment – it supplies its own energy for its own development, efficiently and frugally, through stellar fusion, gravitational collapse, et cetera.

This means evolution should ultimately favour runaway black hole production. (And that checks out: in the most recent estimate, in 2022, by a team from the International School of Advanced Studies in Trieste, our universe was estimated to have already generated up to a trillion supermassive black holes – and 40 quintillion stellar-collapse black holes.)

Indeed! You're right, there doesn't. See my reply above.

I think this cuts through that Gordian knot. "Nothingness" is just an idea in our heads: we have never encountered "nothing". There's no such thing, it's an idea. There is always something; there was always something. And sure enough, in this model, there was always something, some original universe. (Back when it was actually "uni"!) Some unbelievably primitive always-existent universe, made of the original ur-matter, long before the modern periodic table evolved, long before even electrons, protons, and neutrons. All you need is that always-existent universe, time, and change.

How primitive can it be and still reproduce? Because to kick-start an evolutionary process, the only thing that it needs to do is reproduce.

How does a universe reproduce, in this model? VERY VERY SIMPLY. Mass-energy collapses to a point, bounces to form a new universe. All it has to do is collapse. So you have some primitive matter that collapses. It doesn’t have to collapse millions of times and produce millions of offspring (like our universe). Not yet. It just has to do it once. Flip/flop, a collapse and an expansion. A black hole/big bang cycle. And then eventually (and it has infinite time in which for this to happen!), it has to do it twice.

It produces two new universes. There’s two direct collapses that bounce to form new big bangs, new universes, right? And there’s no structure. There’s no complexity. But that’s a direct collapse, forming supermassive black holes. (Which is how, I argue, the supermassive black holes we find today in our universe must still form; evolution conserves successful reproductive strategies, she isn't going to invent a far more complicated way to do it, when a simple way is already available.)

That has to be how the earliest universes reproduced, without complex structures. All they have to do is just be a cloud of totally unstructured ultra-primitive matter, just collapsing. A directly collapsing cloud. No fancy nuclear fusion or stellar masses. And all that more complex stuff – stars, stellar collapse black holes, life, technology, technologically manufactured small black holes – comes later. They are later evolutionary breakthroughs. But they build on that earlier foundation, of direct collapse supermassive black holes.

The universe is the replicator. This comes directly from John Wheeler's old idea, which he came up with back in the 1970s to solve the two mysteries in our universe that involve singularities: black holes, and the Big Bang. I've written about this a lot, so I'm happy to go into more detail:

As an elegant way to solve the two problems, Wheeler proposed that mass/energy in a parent universe collapsed to form a black hole (thus leaving the bubble of space-time that was the parent universe). It then “bounced” at the singularity, and expanded in a Big Bang, to form a new universe – budding off a new bubble of space-time, outside of, and separate from, its parent universe.

That is, parent universes reproduced through black holes, which “bounced” to form Big Bangs. Each Big Bang was therefore the birth of a new child universe, which grew up to produce more black holes; more child universes.

In the 1990s, another brilliant American theoretical physicist, Lee Smolin, saw a marvellous implication of Wheeler’s idea that had been completely missed by everybody (because theoretical physicists don’t usually read much evolutionary biology; Smolin had been reading some, for fun). Smolin realised that if there was slight variation in the basic parameters of matter in the child universe (rather than the large and random variation assumed by Wheeler), you would automatically get Darwinian evolution of universes. That’s because slight variation allows for inheritance; and some of those slight variations would lead to more black hole production; more reproductive success; more offspring. Those successful variations would therefore be inherited more widely than less successful variations. The successful variations would vary again (slightly) in the next generation, with some variants being even more reproductively successful (and some less); and off we go – Darwinian evolution of universes, with the evolutionary ratchet optimizing for reproductive success. Over time, the majority of universes will come to be fine-tuned for very high levels of black hole production (compared to the evolutionary starting point, where the numbers could be as low as one or two). This seems plausible: our universe has already produced over forty quintillion black holes, just from stellar collapse. (That’s 4×10¹⁹; a four and 19 zeros! For how they worked that out, see Sicilia, Lapi, et al, 2022.) Smolin’s simple and straightforward evolutionary theory of universes became known as Cosmological Natural Selection (CNS), laid out in his paper Did the Universe Evolve?, and his book The Life of the Cosmos.

So, Smolin had uncovered a powerful evolutionary implication, hidden inside Wheeler’s simple model of the reproduction of universes.

Definitely worth toying with. Lee Smolin's original idea of cosmological natural selection, of the Darwinian evolution of universes, is about the same age as string theory, and it's just as powerful and interesting a speculative idea. Yet it has received far less attention, I think because it fell between the disciplines, so no field felt qualified to explore it, and thus no field took responsibility for it. I think it's possibly the most neglected major idea in science, and it's almost purely for those sociological reasons, not scientific.

That's a fair point. I suspect that any journalist trying to write about this subject for a respectable mainstream publication (like the Smithsonian Magazine) has to negotiate pretty hard with his or her editor to get the piece to run at all. So a carefully edited secondary piece of journalism like this will tend to be a lot more conservative than the raw primary work it is based on (such as my posts). But that's fine, that's just how the ecosystem works. I'm free to push these ideas as hard as I can, and the mainstream can then sift through them, filter them, and run the ones that seem most solid. That's good, that's healthy! Some of my wilder ideas are very likely to be wrong! In fact, I was surprised to see so many mainstream scientists prepared to be quoted in this piece, even offering cautious support. It feels as though a paradigm shift might be starting to happen.

Yes, I'm familiar with the idea of a Big Bang/Big Crunch cycle. It's intriguing. But, though it too gives you a sequence of universes, its automatic 1-to-1-to-1-to-1 sequential structure doesn't really give you an evolutionary mechanism. I think connecting collapsing mass/energy in a parent universe (a black hole) to expanding mass/energy in a child universe (a Big Bang) makes a lot of sense; even more than a Big Bang/Big Crunch. As the great physicist John Wheeler pointed out in the 1970s, it solves the two otherwise bewildering mysteries involving singularities in our universe! (Black holes, and the Big Bang.) And, because any small variation in the basic parameters of matter means the child universe will generate either more or less black holes (offspring), there is a Darwinian evolutionary ratchet; a reason why universes might get more complex over time, as the ratchet of evolution fine-tunes universes to produce more offspring by whatever means works. (Down three different black hole formation channels, in my model; each more complex than the last, and each emerging from the one before. Strong circumstantial evidence for an evolutionary history!)

Hey, thanks. Fun to be here! I love these ideas, I'm delighted people are interested in debating them.

Sagan is terrific. And it's true that the planets and moons that survive have made it through a pretty brutal era of orbit-clearance. But the evolutionary cosmology model I and others have been exploring is at the level of universes, and is genuinely Darwinian; it gives an evolutionary explanation for why our universe has parameters of matter that allow for the generation of long-term stable planets, and the development of lifeforms on those planets, and the development of technologies by those lifeforms. I would love you to read the Smithsonian Magazine piece and come back to me; it's a beautiful explanation of why universes contain little blue dots at all! I think Sagan would have loved it. Maybe not been convinced by it (it's still a speculative theory, though it is currently having predictive successes), but he would certainly have thought it worth exploring.