It’s a strawman because, for example, you replied to my cites with retorts like “rather than a prediction that we will imminently have them on Earth in a common context” which is not the point I have been making.
(Yes, my own suspicion is that, as long as humans don’t destroy ourselves, we will likely be capable of making SRPs within the next millenium. But it’s not a position I am advocating. It’s not necessary to the point about the Fermi paradox. Let’s say right now that humans will never make SRPs. Fine: it’s irrelevant).
Firstly, it’s not about SRPs being “inevitable”. The point is simply that they are a technology that an advanced ETI could launch, and could visit (and occupy) every star system in the galaxy in a fraction of the galaxy’s age. Perhaps there are a million other technologies available to an advanced ETI that would also be detectable; we don’t know. So before we detect SRPs we detect “schmorgals” instead.
All we know is, we are already aware of at least one plausible technology that could be made by an advanced ETI and it appears so far no-one has (or made anything else detectable). That’s not a data point we should handwave.
In answer to your question: I don’t claim to know. But I think the most likely explanation based on what we know so far is that there are few to none advanced ETIs in our galaxy.
A strange sentence to finish with. I don’t see these hypotheses as being motivated by defending SRPs (or really having much to do with them at all). FWIW, I don’t find either of them compelling; I’ve written quite a lot about the reasons why I don’t think the dark forest holds up, in particular.
Yes indeed. Which is somewhat surprising because we have been able to induce unicellular organisms into multicellular colonies in the lab.
Perhaps the big blocker is cellular differentiation and the embryo phase; it is pretty incredible that a bucket of blobs can form into distinct jigsaw pieces and then fit themselves together.
Anyway, this is fascinating research.
If the galaxy does turn out to be largely devoid of complex multicellular life I hope at least there are complex and different kinds of cells and cell colonies.
Although the most widely accepted solution to the Fermi Paradox is that ‘there is no-one there’, this is not the only solution. I particularly like David Brin’s academic catalog of FP solutions, which includes some of the others we have discussed in this thread, including ‘Interstellar travel is too hard’, which is entirely reasonable given our current state of knowledge.
One solution I am fond of is that advanced civiisations migrate into artificially-produced baby universes somewhere else, so we don’t see them; but it is very unlikely to be true.
John Gribbin hs an interesting book in which he lists numerous ways in which our solar system and our planet are specially suited for life. This might reduce the number of candidate planets from a septillion down to a quintillion or so. Nick Lane finds the venue (“white smokers”) of Earth’s earliest life to be so serendipitous that any alien life probably began in almost the same way! Chop the quintillion down to a mere quadrillion or so.
LUCA, the creature that spawned us all, had spectacular machinery (genetic code, ribosomes, ATP synthase) that required amazing evolution. There are about a nonillion genome replication events every day, but this number was far less when those spectacular machines evolved. And evolving from prokaryotes to eukaryotes seems wildly unlikely. Whales may be smarter than humans but are not equipped to develop high tech.
Were a quintillion random mutations enough to make a species like H. sapiens likely? Is “quintillion” even a plausible guesstimate? Or is the notion that our existence makes such evolution probable just observer bias? I don’t think anyone really knows.
The aliens that have taken over most of Andromeda and are on their way to Milky Way right now are dominated by artificial gallium(?)-based life their carbon-based ancestors designed. They don’t really care if the carbon-based spores take root on new planets or not: The gallium-based mother-ships are self-sufficient, but for reproduction seek resources on new planets. If a mother-ship replicates in 250 centuries on average, they will occupy most of the Milky Way in just 100 million years. They are patient. … If they exist at all.
Time is very much huge. The odds of spacefaring life originating on any given planet are very much small. So we end up with the number
10HUGE * 10-OTHERHUGE
Lotta ways for the resulting number to be either quite hefty or quite miniscule. It’s an (understandable) error to focus on one or the other HUGE and assume its enormousness (big or small) must determine the outcome. Nope.
I don’t think he does. Although he mentions the fermi paradox initially, the rest of the video is about technology that humans could build in the foreseeable future, including an analysis of breakthrough starshot.
When pbs space time have done analyses of the fermi paradox specifically, the hypothesis that high relativistic speeds are not possible isn’t considered a compelling solution.
0.2c is not really a relativistic speed. If you want to take good advantage of time dilation you need to go more than half light speed, and at that speed shielding is very problematic.
One thing I haven’t seen addressed it what happens when you combine the two presumptions of interstellar colonization with species and their civilizations having finite lifetimes. If a previously colonized system becomes empty, is it open for recolonization? Wouldn’t a system’s immediate neighbors be more or less the same species/civilization? If one civilization couldn’t continue to make a go of it in a system, why would another do any better? How does one postulate a civilization dying out if it possesses machines capable of self-reproducing from nothing but raw atoms and their sun’s energy?
That’s one of my questions about Starshot as well. I understand that the project has been put on hold indefinitely. But I’ve no doubt it will be picked up again. but here’s some of the hurdles:
Building thousands of craft that are described as wafers the size of postage stamps, which will house:
Five sub-gram scale digital cameras, each with a minimum 2-megapixels resolution
Four sub-gram scale processors
Four sub-gram scale photon thrusters, each minimally capable of performing at a 1W diode laser level
A 150 mg atomic battery, powered by plutonium-238 or americium-241
A coating, made of beryllium copper to protect the nanocraft from dust, collisions and atomic particle corrosion.
Guidance system
That’s a lot to ask of a postage stamp. Then there’s the laser field. Right now they are projecting that will need 3 km diameter of lasers made up of millions of smaller, precise lasers (e.g., 100 million 1kW lasers). And all lasers must fire in perfect synchronicity (phased array) to maintain beam focus over vast distances. The focused beam of all the lasers must stay focused for millions of kilometers to hit the 4m x 4m sail and accelerate it (and overcoming atmospheric disturbances).
A challenge of those tiny cameras would be sending a signal strong enough to be detected on Earth from light-years away.
And of course, the development of a sail that can withstand the laser’s energy would be challenging.
Then I wonder how much data we can expect from a postage sized “craft” zinging past Proxima B at 20% the speed of light that’s been traveling for 20-30 years.
Not saying it can’t be done, but that’s a lot of technological hurdles to overcome. The pisser is, even if they pull it off, I’ll probably be long dead.
Note that every biological species on Earth is a self-reproducing set of entities, yet the average duration of an individual species is a few million years (shorter for mammals, longer for marine invertebrates). So self-reproduction is not a guarantee of permanence.
Speaking of Permanence, that reminds me of a novel by Milan Ćirković, who has also published academic papers on the FP, just like David Brin. Permanence puts forward the idea that high intelligence in an animal is an expensive trait, and will disappear as soon as the intelligent species engineers a comfortable and safe environment to live in.
Maybe every formerly intelligent species in the universe has abandoned all the existential angst of living in a civilisation, and reverted into post-intelligence, living like a shark or crocodile for hundreds of millions of years with minimal adaption and evolution necessary.
But to work as a primary filter for the paradox, when there’s no reason we yet know of that there couldn’t be millions of ETIs in our galaxy, means they basically all need to act this way. They all need to choose to regress, and do so before doing anything detectable on cosmic scales. Which does not appear to be the course that humans are on.
Hmm; the alternative to post-intelligent Permanence might be even more frightening. Imagine a future where every human is tooled up in a high-tech suit of armour, like Iron Man or Batman, or like the Warren Ellis character The Engineer, who has cropped up in the new Superman movie as a formidable opponent.
Trouble is that the weaponry carried by these fictional entities is sometimes fairly feasible, whereas the protection afforded by such armour is not. A few centuries from now we could all be carrying concealed weapons every second of the day, while wearing armour that affords meagre and inadequate protection. High intelligence might turn out to be a costly arms race, leading to rapid extinction if unchecked.
Post-intelligence might be the only way a highly-capable species can survive for more than a few millennia.
Ćirković’s paper on the FP is here, citing Permanence (which was a novel by Karl Schroeder, not by Ćirković - my bad)
I was editing TVT just now, specifically their Unobtainium and It Runs on Nonsensoleum pages (which, amazingly, didn’t have crosswicks to each other).
Anyway, the kicker is that any advanced race, us or the Borg or whoever, still have to work with the basic elements and their resulting compounds. In even hardish sci fi writers often come up with stuff like Larry Niven’s scrith, or Trek’s neutronium (how it can maintain its structure outside of a deep gravity well is never explained). The so-called Island of Stability still likely has no stable isotopes of any sort.
We also have many examples of advanced tech zooming on to some new level, then remaining at that level for many decades. That kind of plateauing may be the norm, and arguably has been the norm since the first caveman sharpened a stick.
Point is, that, while I am generally sympathetic to the view that deep time may solve most any engineering challenges that we currently see as ball-crushingly difficult if not impossible, that may be an optimistic view. As Scotty himself once said, " *I cannae change the laws of physics!"
I would venture that the vast majority of species become obsolete rather than utterly fail to survive. That is, either conditions change (and how is survival in galactic space liable to change?), or they’re replaced by something similar but slightly better adapted– in some cases they evolve into that replacement. That’s a far cry from postulating that species somehow have an innate lifespan before dying of existential ennui.
At the risk of slightly derailing an excellent long-running thread
Band Name!
Seriously, I agree w your points. IMO terrestrial species evolution is a poor guide to advanced galactic civilization evolution. There’s a lot more to say on that topic but I don’t have the background nor ambition to write the essay that seems the minimum viable contribution.
Terrestrial species evolution is likely to be replaced by artificial evolution in the relatively near future. We will need to establish worthwhile goals for this directed evolution, otherwise it will become a pointless exercise.
