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| Artist’s rendition of what a primordial quasar from the universe’s first few hundred million years might have looked like, with sheets and clouds of gas and dust, stars and early star clusters. Little is known about the details of the astrophysics of this early time, as almost all evidence for it is hidden by these highly chaotic surroundings. It is amid this chaos that our Song of Everything posits the first life emerged. Image credit: Adapted from NASA/ESA/ESO/Wolfram Freudling et al. (Space Telescope European Coordinating Facility) |
Here’s a Rock-solid FACT about the universe we live in:
At one time in the distant past, calculated to be around 15 million years after the Big Bang, our entire universe was bathed in room temperature radiation, such that water *EVERYWHERE IN SPACE* would be liquid.
That was the time when the flash of light that the Big Bang produced—what is now our Cosmic Microwave Background—was at Room-Temperature. It was a Wall-to-wall Goldilocks zone … where Mama and Papa and Baby Bear’s cozy kitchen was a ‘room’ 850 million light years from wall to wall!
But wait. Here come the killjoys … the cautious, conservative, consensus story that science will tell you (i.e., the ‘canon’ that best explains all the available evidence, and so is assumed to be ‘right’ until there is a better story to tell) is that this Enormous Room was nothing but an empty shell.
They’ll tell you that our little nugget of rock-solid fact about a Cosmic Goldilocks Zone doesn’t mean diddly, because 15 million years after the Big Bang we were in the ‘Cosmic Dark Ages.’ No stars had started to form yet. All that existed back then, according to the Standard Model of Cosmology, was an 850-million-light-year-sized bag of gas—consisting of free-floating molecular hydrogen (75%) and helium (25%) and a tiny trace of Lithium bathed in that room-temperature radiation. No water existed then, their story goes, and so *who cares* if it would have all been liquid.
Sorry to disappoint you, killjoys, but your story just doesn’t stand up to simple common sense, so our Song of Everything is here to tell a better story.
We’ll begin with the ‘standard disclaimer’ that our story is just a ‘Song,’ meaning that it is a proposal or a hypothesis based on a wide-ranging common-sense survey of the full, comprehensive bigger picture of what could be out there in such a vast ‘room’ in that early epoch, even if it might seem to be statistically unlikely, and how the very rare events and out-on-the-edge interactions that are neglected by the Standard Model will end up dominating things. Our resulting ‘Song’ just seems to be the picture that most naturally shakes out or falls into place or connects the known puzzle pieces (things not currently explained), including a constant series of new revelations from James Webb Space Telescope of impossibly mature looking very old galaxies.
In Song 28, we noted that life on Earth was already well established just 200 million years after the planet came into its Habitable Zone; and we concluded that ‘Life is Everywhere’ just waiting for our probes to get out there and discover it. Here in Song 29, we double down on that—reaching the conclusion that on Cosmic scales, life is not only everywhere today, but it has been widespread since nearly the beginning of the universe.
To get our story started, we go back to a much earlier time, during that period in which those primordial elements—Hydrogen, Helium, and Lithium—first formed from the agitated soup of early matter called the Quark-Gluon Plasma.
This was the time when matter was first able to form atomic nuclei, and ultimately atoms. The process is called Big Bang Nucleosynthesis (BBN), and the epoch when this happened was super early relative to the 15-million-year Goldilocks era. BBN ended when the universe was just 20 minutes old, yet even then our observable universe was 300 light years in radius—already an absolutely gargantuan space for tiny, rare details to make a huge, huge difference.
What kind of tiny details are we talking about? There are two. One is pretty much rock solid. High precision BBN calculations show that it produced more than just Hydrogen, Helium, and Lithium. There was also a tiny but significant concentration of the heavier elements (like Carbon, Oxygen and Nitrogen), which were large enough, according to the calculations, to affect the formation and evolution of the first stars. The other is the subject left hanging at the end of the level-headed video from PBS Spacetime above—the question of how gigantic quasars could have formed so early. This is the subject of a great deal of scientific interest, and the leading candidate for an answer is a subject that is still barely understood—Primordial Black Holes.
But first, back to the high-precision BBN calculations. The radiation bathing that universe during Big Bang Nucleosynthesis was at a Temperature of 109 to 107 degrees K. This is EXACTLY the same temperature at which hydrogen fusion begins (107 K), Helium Fusion (108 K) and fusion of heavier elements (109 K). The (mostly iron) core of supernovae reach 1011 K when they’re ready to explode. How could this NOT be related to BBN—it can’t be a coincidence. The obvious problem is that this moment in our ‘look-back,’ during which BBN happened, appears to be only a few minutes long (about 20) before the universe cooled and the fusion reactions were stopped, whereas Stellar Nucleosynthesis models show that it takes millions of years at that temperature to build up appreciable amounts of the heavy elements via fusion.
But ***Here’s where the minute details matter.*** The image below is a screen capture of a small part of a recent paper on the high-precision BBN calculations, where the authors discuss the influence of the heavier elements (which they collectively call “CNO”) on the formation of the first stars (called Population III stars):
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Second, if there were Primordial Black Holes (PBHs) back then (even just a very random few), then there could also have been dynamic chaos, such as the relativistic jets emitted from rotating, heavily feeding black holes, from explosive decay of the tiniest black holes evaporating by Hawking Radiation, and from matter being whipped around the deep gravitational wells near and between black holes—all of these chaotic motions can also approach relativistic speeds.
Our Song of Everything points out that the 20-minute ‘look-back’ time is calculated from our ‘stationary’ perspective. Because of time dilation, the relativistic matter in this early chaos will reside in this Goldilocks energy regime far longer than 20 minutes by its internal clock. At the same time, other aspects of the chaos would be generating additional heat to keep the Nucleosynthesis porridge stirring at just the right temperature for much longer. These include density waves from gas cloud collisions, dynamic flows such as the spiral bands in galaxies, and all manner of angry storms and turbulence within this primordial gas … and …
… and almost certainly the formation of some very early stars far sooner than the Standard Model admits.
Even without any Primordial Black Holes, there had to be turbulent flow emerging from the decay of inflation because of the quantum fluctuations—not just the ones that are claimed to exist when inflation began, which are said to have expanded with it into the structure that formed galaxies and galaxy clusters, but those that spontaneously formed during and at the end of the epoch of inflation, making that end an uneven, ragged ‘edge’. These fluctuations would all be smaller in scale, and they are the subject of a recent discussion on Primordial Black Holes that we’re including here for those who want a full immersion at the frontier of today’s research.
This video pretty well covers the state of the art in Primordial Black Hole news. (Wikipedia offers a wider perspective and a pretty comprehensive history of the subject.) At the beginning of the video, the host, Fraser Cain, makes a humble disclaimer that sometimes he was struggling to grasp the ideas that his guest, 29-year-old Indonesian Post-Doc Physicist Jason Kristiano, was discussing. But in reality, Fraser managed to corral and summarize quite accurately the gist of the subject matter. He made only one small error that I noticed—an error that is easy to make. He assumed that Galaxies and Galaxy Clusters formed from the warm temperature anomalies in the Cosmic Microwave Background, when, in fact, it is the cold patches that gave birth to the galaxies because the extra gravitational pull of the denser clumps of matter put a greater drag on the light attempting to escape it, so its wavelength is stretched more.
Fraser kept a lot of the focus on the possibility that Primordial Black Holes could be a candidate for Dark Matter while the guest asserted a commonly held view that PBHs could just be a small part of it. Importantly, there is no evidence for surviving primordial black holes at all, so they’re either very rare or were all very small and have already all evaporated.
No matter. Our Song of Everything’s interest in this discussion is not on today’s quest to explain Dark Matter, but on the very early period before any but the tiniest of black holes would have evaporated, and on the effect that the high-amplitude quantum fluctuations that Jason was talking about would have on the surrounding matter.
Even if these fluctuations that appeared during the period of inflation (or most of them) did not reach amplitudes to produce significant numbers of PBHs, they would still have a significant impact on the post-inflation environment.
As a reminder, the Standard Model of Cosmology is fully dependent on the blanket assumption that Inflation smoothed the Universe at all scales so that it can be assumed to be homogeneous and isotropic. Yet this model *still* allows the first stars to form within 50 to 200 million years after the Big Bang. Our Song of Everything is just demonstrating that all the important anomalies in the tail of the statistical distribution will start stars earlier, never later. We therefore argue that it should be possible and relatively simple to build a bridge on solid piers of additional local star forming zones that might be statistically uncommon but would nevertheless become highly likely across the vast expanses of the cosmos during those ‘Dark Ages’ between the Goldilocks zone at 15 million years, and the Standard Model’s onset of Star Formation.
The picture seems pretty natural and comfortable and common sense, doesn’t it?
Turbulence, shock waves, random flow, and general chaos on star-forming scales seems just about unavoidable and readily stirs the porridge pot; and all this smaller-scale stuff is not adequately represented in the story told by the Standard Model.
Here’s another image, not an artist’s rendition, but a NASA Image from Hubble Space Telescope of a young star forming in a stellar nursery of gas and dust in the Orion Nebula—an object called Herbig-Haro Object 24.
It is exactly those sorts of chaotic environments of molecular (not ionized) gas and clouds of dust and miscellaneous heavy elements that are the stellar nurseries in today’s galaxies and were just about ubiquitous in the early universe!
The flow of all of the discussion above points to a far earlier start to the formation of the first stars. There seems a real possibility, and even a likelihood, that in isolated pockets, stars could, indeed, have begun forming during the Goldilocks CMB period 15 million years after the Big Bang.
Population III stars—these first stars—burn through their nearly pure hydrogen-helium fuel much faster than later stars. Many of them would have gone super-nova in just 2 to 5 million years, releasing great chaotic clouds of the precious heavy elements necessary for life to form.
In the chaos, free oxygen molecules from the stellar explosions (and the few that were formed during Big Bang Nucleosynthesis way back as early as 20 minutes after the Big Bang) would get together with the ubiquitous hydrogen, and water would quickly form. Our argument is that in the statistical tail of the density spectrum of matter during these early times, there could feasibly have already been concentrations of water and the other constituents needed to for life as soon as 15 million years after the big bang.
These ‘small pockets’ with life-forming heavy elements would by no means be small in comparison to individual stars. The evidence for very metal-rich, very young galaxies that is being gathered by the James Webb Space Telescope points to the fact that such ‘small pockets’ could easily be the size of whole galaxies driven by actively feeding super-massive quasars and would contain all the chaos of galaxy-scale Starburst gas clouds. This is exactly the scene depicted in the opening image.
NOW – in Song 28, we thoroughly explored the topic of how quickly life appeared after planet Earth entered its ‘Goldilocks zone’. Here, we extend that argument to these early epochs where far, far more of the universe’s matter existed in Goldilocks zones that could have been as large as whole starburst dust and gas clouds, and perhaps whole galaxies.
We argue that the simple single-celled extremophile life-forms that are known to have gotten a quick start here on earth, would have done the same in countless rocky rogue planets and stellar primordial protoplanetary discs way back then, when the habitable zone was everywhere. Life’s greatest dominance would have been in these early chaotic environments that stretched far and wide across that Enormous Room 850 million light years from wall to wall.
The more rocks that get banged together, bringing with them the raw materials for developing and sustaining life (‘food’ and energy), the better it is for these rugged, hardy microbes.
Life would soon be everywhere. In a timeframe that is remarkably similar to the time it took for life to establish here on Earth (the first 200 million years), it seems highly plausible that life would have proliferated across ALL of our Universe.
All in the first 200 million years after the Big Bang.
And then ... maybe it has been all downhill since. This is a remarkable and surprising perspective. It is arguable that we humans live in the universe’s twilight years—in an era of slow, steady decline in life’s abundance. The era of dominance of the Pan-Cosmic Intergalactic Empire of the Single-cell Microbes (who we have called the “Twees”) may have come and gone long-long ago.
As our universe cools, the Goldilocks zones are shrinking and concentrating and becoming increasingly isolated from one another. Life finds itself huddling closer and closer to individual stars or retreating deep into the still-hot cores of planets.
From the point of view of those robust extremophile microbes, our universe today would seem positively deserted and hopelessly geriatric!
Yet here we are. The ever-adaptable single-celled beings have learned to cooperate to form cognizant, symbolic-reasoning, technological beings—advanced colonies of 30-trillion specialized single cells. Our quick-thinking brains blink on and we look around. Wow! Here we sit in our little goldilocks zone, entirely comfortable, relaxing on our couches.
So … what role for us in this positively ancient, dying universe?
The possibilities are nearly unlimited! We named a few of them way back at the end of Song 21 (see the very end of that long post).
To be sure, we have to take care of our own house first. The universe may already be ancient from the perspective of the Twees, but the future remains vast, and our role in it obviously requires us to not kill ourselves off.
Our immediate role, then—the thing we can do right now and are already doing—is to be the documenter of the workings of this astounding universe. With our symbolic-reasoning minds and the disciplines that the natural sciences have steered us toward, we have established a beachhead of useful descriptive understanding of how a lot of things work.
Our purposes in this regard are three: to continue to discover more, to establish as permanent a record as we can of what we have learned, and to disseminate this record to the “Universe at Large”—by which we mean a place and a time and a way of being that we may not even be able to recognize or comprehend (yet), but which is out there in the realm of nearly unlimited possibility for the future.
Our Comfortable Universe’s Song of Everything now launches into that realm. Again, back in Song 21, we broached the subject with the introduction of Flat World. In other contexts, we have contemplated the Twees and how we humans may partner with them. We’ve talked extensively about Universes having Babies. We have contemplated how Humans might become active participants in Universe Self-Replication, potentially finding ways to transcend our present universe, either physically, or by transmitting the knowledge we’ve gathered, or even a hybrid of the two!
It’s mostly fun at this point, but we always attempt to remain rooted in and constrained by what is physically possible.
And that is why we will always come back to our advocacy for a comprehensive cosmic search and discovery mission. If some other species somewhere in a past universe or in a far-away galaxy, has preceded us in assuming the role of documenters of the nature of our shared existence, then maybe their messages are out there to be found. Perhaps they’re embedded deep in those interstellar rocks that come to visit. Maybe they’re coded in some structure that our universe has inherited, perhaps even in something as abstract as a quantum field. (Is it possible to ‘invent’ a new quantum field and manufacture it in a lab? Have we already done something like that with meta-materials?!)
We will never be done exploring; and you are all invited to come along for the ride.
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