OK, I’ve got a brilliant idea, not yet well expressed. (I tweeted it to a grumpy old man.) Help me make it better.
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!
Hi Julian, this was a pleasure to read as always. I’ve followed most posts now, so the lions share of what is presented here I am familiar with. The one thing that I don’t think has been fully addressed and I have been curious about is mentioned briefly in a note for non-physicists: how are black holes and subsequent universes made for “essentially nothing”? I appreciate your comment about mass energy and gravitational energy being equal, but as a non-physicist I require a bit more rigorous explanation.
This has been a question of mine for almost a year now (I first heard about your Substack and theory over thanksgiving dinner 2022). Until now I had been assuming that the initial universe was just so incredibly (infinitely?) massive that it allowed for the creation of the theoretical trillions+ of offspring universes. I had also been assuming that the black holes, when created were essentially gateways to the child universe, and all the mass in the child universe corresponded with the mass that had been sucked into the black hole. Upon thinking about this more it seems inconsistent with the overall theory, but I had not had another explanation presented to counter it.
Anyway, more explanation of how universes are so cosmically cheap to produce would be much appreciated. I may possibly see you in San Francisco next week. Cheers.
First, Will Kinney's tweet did not deserve such a thoughtful response. Kinney said "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." This is a huge misunderstanding the anthropic principle, which does not require that most of the universe be hospitable for life. Even if only one observer comes into existence, the universe is sufficiently hospitable to be observed. The anthropic principle does NOT say this is the best possible universe for life. It only says that this is at least no worse than the worst possible universe for life. This may be the worst possible universe that can be observed.
Second, if every black hole is a universe, that is very bad news for us. Most black holes merge with other black holes. We have already seen some mergers, with LIGO. If our universe is inside a black hole inside another universe, the probability is that our black hole is orbiting another black hole and they will merge. What happens to a universe when it merges with another universe, with different physical parameters? I don't expect that is amenable to life, in either universe. Smolin's hypothesis does not explain why we happen to be in a universe whose black hole has not yet merged with another. Of course, observer selection would explain that, but then you don't need the rest of Smolin's hypothesis.
Third, this is not the best universe for making black holes. If the strange quark were a little lighter, more of our neutron stars would instead collapse into black holes. This is evidence against Smolin's hypothesis.
Fourth, all discussions of cyclic universes need to consider the nature of time. Smolin believes that time is real and fundamental, but (for example) Hawking believed time is emergent. If time is not fundamental, then there still might be an assembly of universes, but to say that one happened before another makes no sense. In short, the deeper question is whether time is inside or outside of the universe(s). If all the possible universes exist "at the same time" then understanding any interaction between them will require new physics. It may be that the ensemble of universes has a resonance pattern that favors universes that minimally support life. This is the "extremely-strong anthropic principle."
That was a hell of a lot of fun to read and I think is vastly closer than you think. I wonder if you are familiar with the concepts of Constructal Law (proposed by Adrian Bejan -- there's a conference that takes place in Oregon every year encompassing some of the concepts of it). The elements within Constructal Law would certainly impact your proposition. In addition, I was reading one segment and wondering if some of the deformation/mutations of universes could be explained by an occasional small bleed-through from the "parent" universe. Even something on the level of a few particles could throw off the equilibrium, causing greater variation. Or perhaps there is a framework where universes may (stress may) exist in a cluster formation, with very, very minor impacts on one another (the universal equivalent of "sex"). Given that we're speaking about the birth of universes from a black hole into no space/no time, could that be possible? Ending this with just a "great work!" Really enjoyed reading this.
Very interesting. One transition jumped out at me as needing more justification: the claim that a life-supporting universe will eventually have technology to generate small black holes, and that these will vastly outnumber naturally-occurring black holes, thus making the steps that lead up to them evolutionarily favored. My mind immediately asked: just how many technological black holes will there be in a universe like ours? Is it really "vastly greater" than the number of natural black holes?
To estimate an answer that question we need something akin to the Drake equation, with an additional factor to account for "proportion of technologically advanced civilizations that get as far as energy-producing black holes before becoming extinct". (There are times when I think that the odds of our civilization making it to the end of next week are slim.) Of course, this is extremely hard to estimate.
Then we must estimate how many black holes such a civilization would make. Obviously this is also very hard to estimate, but we should at least consider that making and managing energy-producing black holes is very hard and very expensive, and a planet like ours might produce only one or a handful. (For comparison, consider nuclear fusion: if energy-producing fusion reactors are much like current research projects such as ITER, very few countries or international alliances will be able to afford one, and even when the technology is perfected, they may be quite rare.)
Now, one might argue that "rare" is just fine: the overall hypothesis here implies that if it happens once, that universe will have lots of offspring. However, it's not necessarily the case that the rate of construction of technological black holes will grow in the child universes. We should consider the possibility that a universe where just a few technological black holes get built (or even none at all, because technological societies don't hang around long enough to get there) is sitting on a "local maximum" in evolutionary space, and that all the variations in the evolutionary space around that universe are worse for technological black holes, not better. In other words, the universes in which technological black holes dominate may not be reachable in evolutionary steps from this (or any other) starting point.
Anyway, the net of all that is that it's not a "slam dunk" that technological black holes will dominate over natural black holes. Once life gets involved (rather than "just" physics) lots of things can cause evolutionary paths to peter out. So that step, I feel, needs to be justified more strongly.
Morning here and the coffee hasn't kicked in yet. So apologies if this doesn't quite add up, but:
If intelligent life evolves towards making and controlling black holes, and these black holes come to dominate the number of possible universes, does that not imply a high probability that our own universe is one of those? That is, that we, and everything before and after us, lives and dies inside what might be called God's tabletop black-hole power generator? Not quite simulation theory (a fun idea, but I'm not overall a fan), but adjacent to it.
Then, if life /can/ evolve to control black holes - and does so for the purpose of energy generation - both of which sound reasonable to me, why would it seek to create the kind of black holes / universes which are themselves most hospitable towards life? I mean, if the type of black hole determines the type of universe it spawns, why would a species seek to create that particular type? (I guess you could run the argument in reverse.. a universe which creates species which create life-friendly black holes which in turn repeat the process is more reproductively successful.. which places "God" "Himself" within an ur-God's tabletop reactor, and so on).
And on mutation-reproduction-evolution - stating the obvious, mutations don't confer any advantage until they actually result in increased reproductive success. Evolution is generally understood to be lots of small steps (a mix of random and slightly advantageous) that - very occasionally - pass a tipping-point of some kind which opens up big new ecological niches, which lead to bursts of more rapid evolution.
Measured against this, the ability of a universe to create life complex enough to create and manipulate black holes feels like a bit of a "Eureka!" leap, like going from raptors to seagulls in one leap. The way I'm reading your framing, it would take many attempts to produce more and more complex life, but none of those iterations have any reproductive advantage. AIUI, the punctuated equilibria vs steady progress debate in evolutionary biology settled for "a bit of both", with mostly incremental change occasionally opening up a new niche resulting in rapid progress.. what I'm missing, I guess, is why there should be any selection at all in favour of complex-but-not-complex-enough-to-make-black-holes life.
Anyhow... thanks for a fascinating read!
Hi! New reader (and layman) so perhaps I can't find an article or research regarding infinite universes. It seems tautological to me that if there are infinite universes then that alone explains every detail about our own universe. But I haven't seen any evidence that there is more than 1 universe - I had thought that was resolved when hubble found there wasn't going to be a "big crunch". Again, apologies if I'm just not caught up.
sure, that all adds up
Oh now this is good sir, very good. I have been marinating on this all day can't stop thinking about way's to dig even deeper provide even more proof. Let me know if you like any comments and ill notate them down.