The problem of perspective haunts SETI, and in particular that branch of SETI that has been labeled Dysonian. This discipline, based on Freeman Dyson’s original notion of spheres of power-gathering technology enclosing a star, has given rise to the ongoing search for artifacts in our astronomical data. The fuss over KIC 8462852 (Boyajian’s Star) a few years back involved the possibility that it was orbited by a megastructure of some kind, and thus a demonstration of advanced technology. Jason Wright and team at Penn State have led searches, covered in these pages, for evidence of Dyson spheres in other galaxies. The Dysonian search continues to widen.
I cite a problem of perspective in that we have no real notion of what we might find if we finally locate signs of extraterrestrial builders in our data. It’s so comfortable to be a carbon-based biped, but the entities we’re trying to locate may have other ways of evolving. Clément Vidal, a French philosopher and one of the most creative thinkers that SETI has yet produced, likes to talk not about carbon or silicon but rather ‘substrates.’ Where, in other words, might intelligence eventually land, and is that likely to be a matter of chemistry and biology or simple energy?
Vidal is currently at the UC Berkeley SETI Research Center, though he has deeper roots at the Free University of Brussels, from which he created his remarkable The Beginning and the End (Springer, 2014), along with a string of other publications. Try to come up with a definition of life and you may well emerge with something like this: Matter and energy in cyclical relationship using energy drawn from the environment to increase order in the system. I think that was Vidal’s starting point; it’s drawn from Gerald Feinberg and Robert Shapiro in Life Beyond Earth, Morrow 1980). No DNA there. No water. No carbon. Instead, we’re addressing the basic mechanism at work. In how many ways can it occur?
As Vidal reminded the audience at the recent Interstellar Research Group symposium in Montreal (video here), we are even now, at our paltry 0.72 rank in the Kardashev scale, creating increasingly interesting software that at least mimics intelligence to a rather high order. Making further advances that may exceed human intelligence is conceivably a matter of mere decades. If we consider intelligence embedded in a substrate of some kind, it makes sense that our planet may house fewer biological beings in the distant future than creatures we can call ‘artilects.’
The silicon-based outcome has been explored by thinkers like Martin Rees and Paul Davies in the recent literature. But the ramifications go much further than this. If we consider life as critically embedded in energy flows, the notion of life upon a neutron star swims into the realm of possibility. Frank Drake is one scientist who wrote about such things, as did Robert Forward in his novel Dragon’s Egg (Ballantine, 1980). If the underlying biology is of less importance and matter/energy interactions take precedence, we can further consider concepts like intelligence appearing wherever these interactions are at their most intense. Vidal has explored close binary systems as places where a civilization might mine energy, and for all we know, extract it to support a cognitive existence far removed from our notion of a habitable zone.
What about stars themselves? Greg Matloff has pointed to the low temperatures of red dwarf stars as allowing molecular interactions in which a primitive form of intelligence might emerge. Olaf Stapledon dreamed up civilizations using stellar energies in novel ways in Star Maker (Methuen, 1937) and mused on the emergence of stellar awareness. At Montreal, Vidal presented recent work on how an advanced civilization – in whatever substrate – might deploy a star orbited closely by a neutron star or black hole as a system of propulsion, with the ‘evaporation’ from the host star flowing to the compact companion and being directed by timing the pulsations to coincide with the orbital position of each. Far beyond our technologies, but then we’re at 0.72, as opposed to Kardashev civilizations at the far end of Kardashev II.
We have no idea how likely it is that such entities could emerge, but consider this. Charles Lineweaver’s work at Australian National University shows that the average Earth-like planet in the galaxy is on the order of 1.8 billion years older than Earth. The Serbian astronomer and writer Milan Ćirković has made the further point that this 1.8 billion year head-start is only an average. There must be planets considerably more than 1.8 billion years older than ours, and that makes for quite a few millennia for intelligence to develop and technologies to flourish.
Our first encounter with another civilization, then, is almost certainly going to be with one far older than our own. What, then, might we find one day in our astronomical data? I’ve quoted Vidal on this in the past and want to cite the same passage from The Beginning and the End today:
We need not be overcautious in our astrobiological speculations. Quite the contrary, we must push them to their extreme limits if we want to glimpse what such advanced civilizations could look like. Naturally, such an ambitious search should be balanced with considered conclusions. Furthermore, given our total ignorance of such civilizations, it remains wise to encourage and maintain a wide variety of search strategies. A commitment to observation, to the scientific method, and to the most general scientific theories remains our best touchstone.
The specific speculation Vidal tantalized the crowd with at Montreal is one he calls the ‘spider stellar engine,’ about which a quick word. Two types of ‘spider engines’ get his attention, the ‘redback’ and the ‘black widow.’ I assume Vidal is not necessarily an arachnophile, but rather a man aware of the current astrophysical jargon about extreme objects and pulsar binaries in particular. A redback refers to a rapidly rotating neutron star in tight orbit around a star massing up to 0.6 solar masses. A black widow has a much smaller companion star, and the term spider simply refers to the fact that the pulsar’s gravity draws material away from the larger star.
The larger star in such systems can be, spider-like, completely consumed, a useful marker as we study effects such as accretion disks and mass transfer between the two objects. Here is the energy gradient we are looking for in the question of a basic life definition, one that can be exploited by any beings that want to take advantage of it. A long-lived Kardashev II civilization, having feasted on the host star for its energies, could use what is left of the dwindling star at the end of its life to move to another host. The question for astronomers as well as philosophers is whether such a system would throw an observational signal that is detectable, and the question at this point remains unanswered.
Image; An illustrated view of a black widow pulsar and its stellar companion. The pulsar’s gamma-ray emissions (magenta) strongly heat the facing side of the star (orange). The pulsar is gradually evaporating its partner. ZTF J1406+1222, has the shortest orbital period yet identified, with the pulsar and companion star circling each other every 62 minutes. Credit: NASA Goddard Space Flight Center/Cruz deWilde.
We do have some interesting systems to watch, however. Vidal cites the pulsar PSR B1957+20 as having pulsations between host star and pulsar that match the orbital period, but notes that of course there are other ways of explaining this effect. We may want to include this particular signature as an item to look for in our pulsar work related to SETI, however. Meanwhile, the question of stellar propulsion (I think also of the ‘Shkadov thruster,’ another type of hypothesized stellar engine), explored by Vidal in his Montreal talk, yields precedence to the broader question with which we began. Are our perspectives sufficient to look for the kind of astronomical signatures that might be pointing toward forms of life almost unimaginably beyond our own?
On Earth, it seems that the most intelligent animals are the predators. For the being[s] on the star, this implies that there would have been different species competing to drive intelligence, and eventually be able to control their actions or technology to steer the star.
Vidal seemed to dismiss the idea that the active agency could be a simple, unintelligent entity/entities. He claimed that was contrary to evolution, but I wonder if that was simply because it would undermine his argument that such binary stars could move and eventually the consuming star predate on another star for “energy”.
From our “blink of an eye” perspective it will be hard to see these stellivores. If we had a movie of a billion years of stellar movements, such stellivores might be quite apparent as they consume one star after the next. A rather horrifying concept for biological organisms on rocky worlds like us.
Because we are an aggressive species, we project aggression on others. This is the basis for the “Dark Forest” fear of signaling our presence via METI. However, as we destroy ecosystems on Earth we pay no attention to any possible signals from organisms in those ecosystems, including ones that can communicate with us, such as indigenous peoples. A stellivore could be as uninterested in our signals as we are of insects’ pheromones, bioluminescence, and vocalization. Stellivores just consume stars as we consume natural resources.
In my pantheistic moods, I wonder what ripples or waving wheat fields are calculating.
Some optical diffusers look like veins of ore
https://www.google.com/amp/s/phys.org/news/2023-10-morpho-butterfly-nanostructure-technology-bright.amp
Confessions of a carbon chauvinist
In its liquid state, water is an extremely efficient solvent in a temperature range where highly complex molecular structures are possible. Carbon is capable of forming highly complex molecular structures in the presence of liquid water. Water, carbon and suitable conditions are abundant in the universe. Our only example of life, right here on earth, is widespread on our planet and has shown itself to be ubiquitous, adaptable, robust and resilient. We don’t need exotic and alternate biologies based on silicon, stellar plasma, neutron stars or other speculative forms of organizing the matter-energy processes we call “Life”. Even if these entropy-defying processes can exist (which we really don’t know), carbon/water based life is probably common throughout the universe. We need not propose exotics in order to guarantee a universe with plenty of potential SETI possibilities.
Our means of identifying the signatures of “Life” (whatever that is) or its technological artifacts at interstellar distances are not dependent on the chemical pathways the creating form of organism or civilization has utilized. They will distinguish themselves by being inconsistent with normal astrophysical processes.
Again, it is not how life arises, or its origins that really matter, and we need not speculate on exotic alternatives to carbon and water.
I’m not saying these exotics do not exist, or that they can’t possibly exist. I just think it makes no difference. As for the possibility that alien life might manifest itself in ways we cannot possibly anticipate, I suspect that even the most recognizable and conventional chemical life form will be totally surprising and unexpected in its behavior and motivations. They are going to be strange, regardless of their biochemistry.
My problem is with the supposition that the stellivores are naturally evolved “life”. It seems far more likely that the intelligence uses some physical substrate and that it was created by technological biological life. Once created, it/they could harness these binary stars to create the energy they want and to perhaps steer they system to intercept another star to consume or transfer to another similar binary star.
While Forward and Baxter have both written stories where there is life on neutron stars, there is no hint of how life could appear and evolve on these stars. I find this life as improbable as the giant worm in Star Wars living in an asteroid.
It’s valuable to look for traces of an abiogenic origin. After all, Earth life is not very different from a primordial formose reaction creating ribose from formaldehyde on hydroxyapatite. In the case of a “stellivore”, I’ve speculated in some recent comments about graphene-based life in space. Searching “c60 star” on Arxiv yields an abundance of interesting papers, such as https://arxiv.org/ftp/arxiv/papers/1904/1904.10140.pdf (Ota, 2019) comparing known and unknown absorptions of carbon stars not just to fullerenes but graphene more generally. Question: can similar carbon structures begin to catalyze their own growth and develop the logic elements to regulate their own reflection and absorption of light or magnetic interactions to the point where they can preserve themselves, replicate, and accumulate genetic improvements? However, I’d think neutron stars would be as deadly to graphene life as they would be to humans – I’d expect such life might prefer dimmer stars with more massive and long-lived sunspots, carbon stars, perhaps dusty stellar neighborhoods and stars that emit strong stellar winds.
“Unconventional” (by our conventions) life may be difficult to conceptualize, and therefore to recognize. Control mechanisms will be operative for interacting streams of matter and energy appropriate for sustaining mechanisms of sufficient complexity at whatever scale the system functions.
Disruptions in matter and energy, if recognized, could be clues to “alternate life”. And even intelligence, if emerging from such an alien substrate, may manifest in ways nearly beyond our ken.
I’ve been saying this for years (about alternative substrates)! Assuming alien life would be anything like us has always seemed like a reach to me.
An interesting thought experiment: what if alien life was _already_ in our solar system… but we simply haven’t noticed it because we’re looking in all the wrong places. Where would it be?
There have been a number of posts on ETI in our system and where we might look for them. e.g. Jim Benford’s Comments on METI.
We are restricted to looking for artificial objects. But what if they are not largish physical artifacts? If they are small we cannot detect them. If they are natural-looking, they would be hard to detect. If they are immaterial they would be impossible to detect. And the sci-fi trope – what if they are hidden among us?
All we can do is make assumptions are start looking.
Even artifacts may be hard to find, for example, if they are buried of hidden in natural objects. Recall that Kubrick/Clarke’s lunar monolith in 2001: A Space Odyssey, was buried, but made detectable by a huge magnetic field – Tycho Magnetic Anomaly 1 (TMA-1). Without that magnetic field, it would remain undiscovered. In the final novel, 3001: The Final Odyssey, the African monolith that was manipulating Moonwatcher’s hominid tribe, was discovered during an archaeological dig, not by some field emanation, long after TMA-1 was discovered.
There is a phys.org story called ‘Evolving’ and 3D printing new nanoscale optical devices
Here, the optics don’t even look how I imagine optics to be:
https://phys.org/news/2023-07-evolving-3d-nanoscale-optical-devices.html
Such an odd look… maybe a probe can look like a rock.
“Matter and energy in cyclical relationship using energy drawn from the environment to increase order in the system” seems like a poor definition of life. A fancy wristwatch that self-winds by hand movements would be an example of this. Earth’s water cycle or Mars’ CO2 cycle would be an example. Mars even shifts the CO2 neatly from one end to the other – surely a nice illustration of how to tidy up a messy pile of dry ice.
The way I’d like to define life would be in terms of homeostasis, especially states defined by negative feedback. Life is a set of interacting processes which influence the rate of one another to produce a controlled (typically “internal”) environment. The more processes, the more alive something is: a house with a working thermostat and furnace is one binary bit more alive than one without. Throw in circuit breakers, water pump and reservoir tank, burglar alarm, and an internet service run from a local powered server set to reorder the fuel and pay the electric bill, and the house starts to seem like it has a bit of a life of its own. An injury that throws a breaker, knocks the furnace offline, and freezes/bursts the pipes over the computer might “kill” it. Of course, even a bacterial cell has vastly more bits of “life” than this, including thousands of genes each of which regulate one another’s activities.
Also, the universe can be neither cyclic nor have a beginning or end – it may merely be logarithmic. When we look back to the Big Bang, things happen ever faster and hotter; when we look forward, ever slower and colder. But by the standard of any given era, a particle moving the diameter of the known universe is in for a long, strange trip indeed – many interactions along the way! Why shouldn’t the universe have an endless succession of novel eras, characterized by different particles following different laws of physics at different time scales? Someday neutrinos will have had long enough to pull themselves into clusters by gravitation and perhaps more interesting forces, and perhaps life will somehow exist among them… until those comparatively dense and short-lived neutrinos break down into something new. Something we can’t hope to have seen in this first instant of the Big Bang that we’ve evolved in.
Asteroid 33 Polyhymnia.
A little off the beaten track but what may be a Tecno signature right in our back 40. Something that breakthrough initiatives may want to do a limited research on… If true, a definite possibility of microscopic black hole or alien technology.
Beyond the periodic table: Superheavy elements and ultradense asteroids.
https://phys.org/news/2023-10-periodic-table-superheavy-elements-ultradense.amp
Without being able to read the paper, I wonder if there is an issue with measuring the mass and/or volume of the asteroid. Volume would be measured by brightness, and this may be incorrect, assuming a smaller asteroid than it is. As for mass, how was this measured – by some gravitational perturbation of another object? Unless both values are correct, then the density may be incorrect. I assume the paper has the details.
If you read the paper, can you explain how they were able to measure the density of this asteroid?
The paper is about what elements could make up a ‘compact ultra dense objects’ (CUDOs). Their calculations agreed with the island of stability previously predicted to reside at atomic number 164. And they showed that the density range of this element sits between 36 and 68.4 grams per cubic centimeter. That’s close to that high density calculation for 33 Polyhymnia.
Consider compact ultra-dense objects (CUDO) meteors made predominantly of ultra dense matter such as STRANGElet = fragments of neutron stars filled with strange quarks, DARK MATTER bound objects, MICRO BLACK HOLES or super heavy elements.
Due to its high eccentricity (0.338), one of the highest for a lower numbered minor planet, on rare close approaches it can reach tenth magnitude, as on September 8, 2014, when it will be apparent magnitude 9.9 and 0.894 AU from Earth. The orbit of 33 Polyhymnia puts it in a 22:9 mean motion resonance with the planet Jupiter. The computed Lyapunov time for this asteroid is 10,000 years, indicating that it occupies a chaotic orbit that will change randomly over time because of gravitational perturbations of the planets. Measurements of the position for this asteroid from 1854 to 1969 were used to determination the gravitational influence of Jupiter upon 33 Polyhymnia. This yields an inverse mass ratio of 1,047.341 ± 0.011 for Jupiter relative to the Sun.
Polyhymnia has been studied by radar. The mass was found by gravitational perturbation of it by Jupiter. In 2012, a study by Benoît Carry estimated a mass of (6.20±0.74)×1018 kg for Polyhymnia based on its gravitational influence on other Solar System bodies. However, given Polyhymnia’s diameter of 54 km (34 mi), this mass implies an extremely high density 75.28±9.71 g/cm3. Such a high density is unphysical, so this mass and density estimate of Polyhymnia is considered unreliable by Carry in his study.
So is it made of Unobtanium? That is why another study should be done with AI’s help to find a more accurate density for the object.
Are the mass and “given” diameter accurate, or subject to error?
When a density seems unusually high, leaping to a super dense element as an explanation seems less likely the correct explanation than that there are errors in the mass and volume estimates.
OTOH, maybe it is made of normal elements, but with a tiny black hole in the center?
There are several ways that improved data could help figure the density of these objects, the GAIA measurements of asteroids and the many wide scale surveys of asteroids since 2012. The observations of these objects from radio to gamma-ray plus cosmic rays could be a indicator of exotic matter or micro black holes. Here is the “Density of asteroids” by B. Carry from 2012;
https://arxiv.org/abs/1203.4336
A very good 58 page info graphics on CUDOs with the denser asteroids listed on page 36.
https://indico.wigner.hu/event/965/contributions/2172/attachments/1763/3125/Rafelski_Balaton2019.pdf
Some interesting developments on “Traversable wormholes.”
Traversable wormholes with static spherical symmetry and their stability in
higher-curvature gravity.
https://arxiv.org/abs/2308.11004
Simple method to generate magnetically charged ultra-static traversable wormholes without exotic matter in Einstein-scalar-Gauss-Bonnet gravity.
https://arxiv.org/abs/2310.08758
From the Wikipedia entry for this asteroid:
TL;DR – the explanation is a measurement error, rather than a superheavy new element. Just as ‘Oumuamua is most probably a natural object and not an alien spaceship, this apparently anomalously heavy asteroid is more likely to be a regular asteroid that has a large measurement error for its mass. The arxiv paper on asteroids indicates great uncertainty of the measurements of a number of asteroids. One chart shows asteroids with densities approaching 12, suggesting they are heavier than nickel-iron, but all are small and therefore likely to be incorrectly measured. We just launched a probe to 16 Psyche, a metal-type asteroid that has an estimated density of about 4, less than iron, even though it is expected to be similar to the cores of rocky planets.
I would love to have an alien artifact in our terrestrial backyard, but so far, all supposed alien technology seems less real than the Yeti, Sasquatch, or Nessie. Despite the claims of Von Daniken (and the interminable BS on the US History cable channel), we are pretty sure the ancients were able to build pyramids without help from ET.
If we keep looking, we might find something extraordinary. However, I think the possibility is very remote.
Interesting scenario! The usable link (LaForge, 2023) is https://arxiv.org/pdf/2306.11989.pdf . It looks like a welcome improvement to some notions we see at https://en.wikipedia.org/wiki/End_of_the_periodic_table (Wikipedia suggests that atoms with more than the inverse fine structure constant of protons can’t exist as neutral entities, but doesn’t explain how you would shoo an electron away from a positively charged object). LaForge discusses not just the filled nuclear shell of Element 164, but “alpha matter” with loosely associated nucleus alpha particles mixed into their inner electron shells to screen out the positive charge. I don’t understand what sort of baling wire (other than extreme cold) could hold that together, but it’s described in https://arxiv.org/pdf/2304.08543.pdf .
That said, I can’t picture finding an entire natural asteroid made exclusively from exotic elements astronomers don’t see a single atom of anywhere else, including in any stars they might have fallen into. Either Polyhymnia’s statistics are calculated or compared erroneously … or it’s not of natural origin. Heck, I’d be happy to discover an asteroid with a density of 19.3 and a distinctive glint, but if we find such a massive nugget I doubt that would be of natural origin either.
Hello,
Just a quick comment to pay tribute to Hubert Reeve. He said, “Man must learn to master his formidable technological power or humanity will destroy itself”…
Fred – France
There seems to be conjecture aplenty on islands of stability elements but getting past the conjecture is yet awaited.
Hello,
Reading the various comments, I think it’s worth making a distinction: either we’re looking for a form of life in the universe, or a techno-signature. But what exactly do we mean by this term? An assembly of chemical compounds is not really a “techno “signature, e.g. the amino acids of life in our form. We could also consider that a significant multiplication of these “natural” compounds could be the manifestation of an “intelligence”, although we’d have to define this word (I’m thinking of the proliferation of mosses in forests or mushrooms).
This is a completely different line of research if we consider, for example, a structure like a Dyson sphere. Indeed, we then have a construction, which implies an “intelligent” organism, that is to say, capable of reasoning to model its environment for a specific purpose. There is therefore a determinism.
For example, building an ARTIFICIAL structure to protect yourself (a shield); to hide (these spheres); to move in interstellar space (a spaceship) or to communicate (a telescope). A techno-signature can also indirectly result from a structure that we cannot perceive: we have all seen the ISS in the sky, not directly with the naked eye but by the reflection of light on its solar panels! This is a technosignature !
now, consider the ISS abandoned by its crew and no longer emitting any radio signals, in orbit around the earth: an ET could then still perceive this technosignature, this reflection, for a certain time and possibly on a regular basis, leaving to think a form of intelligent life, but will never be able to know that we are there and even less communicate with us!
if we add the intergalactic distances to perceive this signal, the research would not really make sense and would surely be very disappointing. In other words, should we first look for the life that develops technology, or a technology that will allow us to discover a form of life and, better still, an advanced civilization?
A RANDOM proliferation of an assembly of simple chemical compounds that could be found anywhere in the universe does not necessarily mean an evolved civilization wishing to communicate with us. Basic chemical compounds; simple organic life then complex then Technology: I think we need to define what we are looking for and at what point in this chain of development we are looking for it.
I don’t know if I expressed myself well because ultimately, we are limited by our language to define certain concepts (“life”; “intelligence” etc.) which make it possible to give meaning to the World. Also, I think that the search for ET intelligence requires us to set a precise philosophical research framework to know what we want to find.
Fred – France
Are you familiar with Dawkins term – The Extended Phenotype? This can vary from simple things like nest building to Dyson spheres. If we detect on an exoplanet an unnatural arrangement of plants and ecosystems, that would indicate intelligence of some level. Simple compounds that can only be synthesized artificially would also count. Suppose we decided that our space stations should be covered in wood or some other natural material? Even a wood space station would be obviously unnatural and therefore a technosignature, just as wooden sailing ships were.
Just as we look for disequilibrium in atmospheric gases to possibly indicate life, so should arrangements of almost anything that is a departure from natural processes. Life, of course, creates many things that are artificial even if the intelligence to create them is not particularly high – like termite mounds. Some things are more obvious, and a signal of prime numbers would, AFAIK, be clearly artificial.
I had the impression that “The Extended Phenotype” referred to those features or characteristics controlled by a genome that are outside the organism in which that genome resides.
The color, shape and fragrance of flowers, although under proximate control by the plant’s own genome, had that control modulated by the genes in pollinators that made those features attractive to thepollinators.
Other examples include mimicry, and the persistence of lactase into adult life in pastoralists, resistance among small New World mammals to rattlesnake venom (but not Old World snake venom) and the resistance of Old World mammals to the venom of snakes in their milieu (but not to rattlesnake venom).
How about the alien equivalents (of what’s left after a billion years) of beef jerky, a USB thumb drive, a toothbrush, a sneaker, a smart credit card, et cetera? The smaller the item, the more likely its complete disintegration. Yet if well preserved, any one such item could answer Fermi’s paradox. Sans philosophy.
This we know, with a high degree of certainty:
The chemical precursors to life are plentiful and widespread.
Multiple stars and planets are available for its development.
On Earth, life seems to have arisen as soon as the planet cooled off.
Life survived and flourished even as the planet changed and evolved.
Life is now everywhere, even in environments we once thought deadly and toxic.
I suspect life is abundant in the universe.
What follows is more speculative
Multicellular life capable of supporting intelligence arose relatively late in earth’s history. This suggests it is rare in the cosmos, and is to be found only in very old, relatively stable, stars and planets which have somehow eluded nearby cosmic catastrophes.
Intelligent life arose here only a moment ago, in cosmic terms, in a very old planet around a very old star.
Intelligent life appears to be unstable, evolve very rapidly, and is dangerous to the biosphere it inhabits as well as itself.
Intelligence may allow a species to recognize this and rapidly learn to manage its activities to reduce risk to its environment. But it hasn’t happened here yet.
These considerations suggest intelligent species in the galaxy are separated by vast distances in both space and time, and rarely (if ever) actually meet one another or communicate.
We have no way of knowing if the development of technology leading to space travel and communication is inevitable, or even common, among intelligent species. In our case, it seems to have arisen very late in our history and is riddled with destabilizing and dangerous by-products.
This suggests only a small proportion of the intelligent species that DO exist will develop the technology or the desire to seek out their fellows in the galaxy.
I have no direct or conclusive evidence, but I suspect we are alone. If not, We will never meet our brothers. We are continents, and eons, apart.
I certainly hope my suspicions are mistaken. But that’s the way it looks like to me now. I have no way of saying for sure, and I certainly have no conclusive evidence, but I’ve spent a lifetime thinking about this and this is the way it looks to me.
“I have no direct or conclusive evidence, but I suspect…”
It is unwise to extrapolate from a single example. It is, at best, suggestive and perhaps useful for hypothesis generation, but not if those hypotheses are untested. A single example as a basis for statistical analysis? No.
“Intelligent life appears to be unstable, evolve very rapidly, and is dangerous to the biosphere it inhabits as well as itself.”
This is not unique to intelligence. Countless species over the eons have pushed out other species from a environments or have made a previously diverse environments into near mono-cultures. That’s just evolution at work through the efforts of mindless creatures.
But in our case we have a choice, because we’re intelligent. I believe that’s a positive development.
“It is unwise to extrapolate from a single example.”
Absolutely. And we only have a single example of a species capable (perhaps) of interstellar travel and communication. If the galaxy is densely populated with sentient creatures capable of interstellar commerce, we don’t know that, and we have no way of knowing that.
We DO have circumstantial evidence that suggests microbial life is common on other worlds, although even that is tenuous, at best. We need a new Drake Equation that considers the probabilities that
1) Multicellular life can easily arise
2) Intelligent life will arise
3) Intelligent life will develop a physics-oriented technology
4) A technical civilization will actively explore and expand into space
5) Sufficient planetary systems will remain stable long enough for these things to happen, and continue happening, for long periods of time, in a lot of different places.
So far, the SETI community has simply assumed that extraterrestrials will be aggressively expansionist gadgeteers, just like us. At the very least, that appears to me to be a very anthropocentric assumption, not a wise strategy for speculation on this topic. And most of all, we have failed to consider the possibility that even the most accomplished spacefaring civilization will soon come to realize that that once you’ve settled a few nearby worlds, and explored thoroughly several others, the universe is pretty much the same all over: lumps of slag and ice orbiting dim red suns.
The really interesting places will be too deadly to approach. Once you have protected your civilization from extinction, and assured its survival against cosmic catastrophes, further expansion is pointless and expensive. There are many other worthy goals for a culture to spend its resources on.
Keep in mind, I’m not saying we are all alone. I’m just saying there are so few of us, and we are so far apart in both space and time, it is highly unlikely any of us will ever stumble onto another.
Oh, and one more thing. Suppose a civilization does manage to contact one of its neighbors. Even if the relations between the two are friendly and productive, all of their efforts will be directed onto carrying out that relationship, not seeking out new ones. Who needs multiple pen pals, anyway?
I suspect that on many of those hypothetical spacefaring civilizations, the leadership will be thinking; “We finally have reached the point where our culture is sufficiently dispersed and protected from accidental extinction. We are probably secure for the foreseeable future. Why risk further expansion; who knows what hostile, aggressive or otherwise potentially disruptive creatures and philosophies might be lurking out there?”
Wouldn’t it be more logical to send out emissaries to determine if distant civs are potential allies or enemies? If allies, that strengthens both civs, and if enemies, then prepare to defend your civ. Deliberate ignorance doesn’t seem like a rational strategy to me. Are there any terrestrial historical examples that could be instructive?
Emissaries are risky because the aliens might take them apart to figure out where they came from. Isotopic abundances, mind downloading, thumbscrews… whatever works. It seems safer to use emissaries who don’t know where they came from — but those should have an impeccable backstory. A good strategy might be for a stealth probe to find some planet with indigenous primates that have a preexisting tendency to scream from the treetops. Use GMO-free selection methods to engineer sapience, then wait for the newly elevated species to yell “Look at me!” to the universe. When enemies go there, study their weapon systems from a distance with some very large telescopes.
Have you thought of working in a Dept. of State or Ministry of Foreign Affairs? Are you a good Risk player? ;-)