“Where are they?”, Enrico Fermi
George Rebane
Since my previous foray into Fermi’s famous query, I have had occasion to reconsider the numbers that I generated when first applying copernican arguments to the sound of silence experienced by the various Search for Extraterrestrial Intelligence efforts that started about the middle of the last century. My conclusion was that, the albeit the dismal results I introduced on my blog (here) to explain away the SETI experience, these were still too hopeful. This work definitely made me a graciously tolerated philistine among the dedicated throngs searching the heavens for evidence of ETI. Unfortunately, what I present in the sequel will only reinforce my reprobate status.
As a result of that first investigation I was nevertheless fortunate and honored to be invited to join the informal group of SETI researchers by Dr Andrew Siemion, director of the Berkeley SETI Research Center at UC Berkeley. Becoming more familiar with some of the ongoing efforts and literature generated by the hard-working stalwarts of that international cohort of professional astronomers, cosmologists, astro-physicists, …, I was motivated to return to the drawing board for another look at how we may explain the lack of success from so many ‘eyes’ pointed at the heavens for so many years, all collecting reams of data comprising mostly of inter-galactic and inter-stellar noise layered on the ubiquitous hiss of the cosmologic background, always there to remind us of our origins. And all this from a galaxy that has spawned hundreds of millions of ETI civilizations and, most likely by far, is still teeming with most of these. So why have we had no contact with them? This is the perplexing Fermi Paradox.
To answer that question, support for a copernican perspective and approach to SETI were presented in ‘A copernican answers Fermi’. (For other answers, read this.) To review some of the salient factors, we again consider that we live in an 13.5G year-old galaxy that formed along with billions of others in that epoch after the Big Bang of 13.8G years ago. The Milky Way (MW), containing north of 200 billion star systems, gave birth to our sun and its orbiting planets about 5G years ago. Today, by all counts, we see that the MW is an ordinary galaxy like billions of others, and our sun is a very ordinary G-type main-sequence (G2V) garden variety star. And its inventory of planets is of the type and with orbits replicated by eleven billion more exoplanets throughout the MW and countless other galaxies. In short, there is no a priori reason to believe that we are anything special in the universal scheme of things – ergo the copernican perspective.
Interested readers can download a copy of the follow-on study here - Download TN2002-1v200221 .
Ya know, it seems to me that if ETs are difficult/impossible to find given the statistics of technocratic life arising, distance, and a short lifespan of detectable evidence due to advancement beyond it (which could be as simple as directional communications plus the difficulty in plucking signal from randomness.. up to singularities), perhaps the best way to find the beasts is by looking for astronomical features that can't be explained by straightforward physics.
Somebody must have built something large, maybe just for art's sake.
I admit that if aliens simply produced Von Neumann versions of Voyager probes, the evidence would be everywhere.
Posted by: scenes | 16 February 2020 at 10:07 PM
And then there's the remote, heretical possibility that we really are the first to reach this point.
Perhaps God wants to see how Homo Sapiens turns out before infesting the rest of his creation with more of us...
Posted by: L | 17 February 2020 at 08:32 AM
"the remote, heretical possibility that we really are the first to reach this point."
I'd say that reaching this point was never a sure thing. Really large scale organization followed by engineering and bonafide science mostly swept out of a few hotspots, and perhaps out of only one (seeing as how they were so close in time). Most of the planet's humans would likely have happily kept on doing what they were doing, smallest scale metallurgy, wheels for childrens' toys if lucky, for another 50k, 100k, etc years. Perhaps even go backwards. Primitive culture can be remarkably stable.
It doesn't seem to me that human level intelligence necessarily implies technology.
Posted by: scenes | 17 February 2020 at 08:53 AM
scenes 1007pm - A most plausible habitat for post-biologic ETI is the Dyson sphere in any one of its manifold configurations. I am of the school that doesn't see much profit in sending out Von Neumann probes. Accelerating technology in all developing ET civilizations (including ours) will quickly make moot the spraying such probes into the galaxy - there will arise the ability to fry bigger fish.
Primitive cultures are probabilistically 'stable' only in environments benign in the supply of shelter and food - witness the location and number of such rare instances on our planet. But even then - if we can assume the copernican view - critters tend to screw things up on a societal scale by becoming autocratic cum tyrannical. This gives rise to dispersion and innovation as demonstrated by our tropical and Polynesian brethren.
Posted by: George Rebane | 17 February 2020 at 09:45 AM
"I am of the school that doesn't see much profit in sending out Von Neumann probes. "
Well, the thing is that it only takes one of innumerable civilizations to do it, and they would outlast the sending party given your concept of 'pulse'.
Primitive cultures. Indigenous Australians aside (the perfect modern example of 50k years of stasis), I'd say that stone age humans can last for 100k+ years with little increase in technology. The moment you can work with wood, animals, the crudest form of agriculture, flint, and a bit of pottery, you can make a pretty good living for yourself in most climates...or good enough anyway. My gut tells me that the modern world is either an accident or the result of some physical change in a small group of people (also an accident).
Just thinking about SETI. Given the rise in MFLOP/$$$, it would be interesting to see how modern approaches work. Dunno what a data training set would look like. Do SETI guys ever look for unnaturally *random* data? Both compression and encryption would lead to that and for all I know there's a footprint to 'artificially random' data that you don't see in the natural world.
Posted by: scenes | 17 February 2020 at 01:33 PM
*footprint because I figure that aliens don't have traditional hands.
Posted by: scenes | 17 February 2020 at 01:41 PM
scenes 133pm - given our normative rate of technological development, the interval for sending out the probes will be very small before better means of sending out messages and/or getting there become available.
I think that H. sapiens migrating into temperate climates was all that was necessary to start our ancestors' creative juices cooking giving rise to all kinds of clever solutions and inventions.
Not sure how you use 'pulse' in conjunction with what I have described - does pulse = ripple?
Posted by: George Rebane | 17 February 2020 at 01:53 PM
As I understand 'pulse', the idea is that there's a short time period, likely expanding at light speed, where intelligent civilizations are observable.
Before radio (or simple electrical generation for better instruments), ya got nothin'. After a singularity, maybe ya got nothin'. That time period is a pulse. Perhaps you mean something different.
In terms of probes, the probe could itself be intelligent of course. The idea of reproducing devices of any kind, much less one with cognition, is so powerful a concept that I'm surprised the universe even exists at this point. All it takes is one culture, perhaps as a practical joke, to release the paperclip making machines.
Posted by: scenes | 17 February 2020 at 02:06 PM
scenes 206pm - perhaps you didn't read my first paper and look at the figures. Your understanding of 'pulse' appears equivalent to an emitted ripple of a given duration, say, a couple of hundred years or so experienced at a point. We tend to think of pulses (in, say, electronics or astronomy) as having a much shorter duration, hence I use the more descriptive term of 'ripple' to describe its shape in the galactic plane, and its thickness (L in the literature) in the years of EM transmissions issuing from a ETI planet. And you are right, the only time we can capture evidence of such an ETI is when we are fortunate enough to be in its ripple before it 'blinks out' forever. It is the data gathered from the ripple that gives us hope of obtaining reasonable values of P(R,S,D,C). As I make clear in my technical note, I am only introducing a new method with which to estimate P(R) as shown in eqn(1) of the TN. And plugging in some reasonable values for the needed variables, the outlook for our experiencing a ripple doesn't look good. Not news people who fund and operate huge radio telescope arrays for SETI purposes want to hear.
Posted by: George Rebane | 17 February 2020 at 02:43 PM
ah, I see what you mean in terms of wording. My own thinking was that a ripple is a series of similar events, or a causality set, while a pulse is a single event (except in heart beat hopefully) like you'd see in an individual short flash or sound.
I suppose that in the most exotic version of singularity, a kind of intellectual godhead, a lot depends on whether there is any value in extrasolar knowledge or material.
Posted by: scenes | 17 February 2020 at 03:34 PM
"Not news people who fund and operate huge radio telescope arrays for SETI purposes want to hear."
It seems to me that an interesting way to finish up this kind of calculation is to work out the ROI of the SETI research. What is a range of long term value (including odds of success of course) vs. an estimated cost of a proper effort.
Posted by: scenes | 17 February 2020 at 07:54 PM
Scenes 754pm - Interesting task. To make the result more widely acceptable, we have to quantify the utility of a successful search. That utility will necessarily be a subjective formulation (as are all utilities). Care to offer one for consideration?
Posted by: George Rebane | 17 February 2020 at 08:05 PM
Considering just how much info governments make damned sure(at least try to) is covered up good and buried, we ain't "alone."
The latest "leak" is pretty good evidence.
Something else to think about. Where did all the people go from those "lost" civilizations? You know,, like the Inca and South American cultures that seemingly just disappeared?
Harvested for "food"? of cheap labor somewhere else?
Posted by: Walt | 17 February 2020 at 08:28 PM
Walt 828pm - You apparently don't think that war, famine, and disease were up to the job of killing those civilizations.
Posted by: George Rebane | 17 February 2020 at 09:02 PM
Walt, those civilizations didn't 'disappear', but dwindled to historical status; the people mixed with the Spanish to create a heretofore unknown 'race'- which we call Hispanic. Those who resisted were largely exterminated. Has happened many, many times in world history- perhaps to every civilization outside the current mainstream.
Posted by: L | 17 February 2020 at 09:10 PM
Oh, it's very plausible natural attrition is the reason.
But even that is speculation. tens of thousands of people just up and gone. That's the "book learned"
educated way of thinking. Ever think outside the box?
The "book learned" explanation of this is?
https://www.businessinsider.com/navy-pilot-tic-tac-ufo-interview-aliens-2019-12
Are we alone? The odds are pretty damned good the answer is no.
Besides. I have seen some real unexplainable things myself.
Nope,, not swamp gas or Venise. (nor good drugs)
Posted by: Walt | 17 February 2020 at 10:21 PM
re: variations on Dyson spheres.
If access to energy is the thing, and the local star is the way to go, I can see where those would evolve. A cloud surrounding a star, perhaps with the rich lying closer in. A hard megastructure doesn't sound like there's much point. No doubt someone has peeked for infrared signatures of such things.
On ROI, I think people overstate the value of discovering life elsewhere, either microbialesque or 10k LY off touching us with their version of old I Love Lucy shows. It would run on the news for a week followed by some new parochial outrage about politics. There's always the hope for mining technology, but I think that requires the yet-more-unlikely setup of bidirectional communication.
I do have to wonder what, given an unlimited budget, sort of instrument construction and computer HW/SW could be applied to the problem.
Posted by: scenes | 18 February 2020 at 12:36 PM
scenes 1236pm - Actually, the interests of post-Singularity lifeforms are hard for us to fathom. I make no claim to such a skill, since I know that I cannot think all thoughts, and most certainly not the thoughts of super-intelligences. But I do embrace dearly the copernican concept that the confirmation of a galaxy full of ETIs will have an equivalent impact on human thought (beliefs, values, mores, concept of self, ...) as did the revelation that the universe was not geocentric.
And I do believe that the discovery of or first contact with an ETI will occur in this solar system, and most likely on Earth. Vast radio telescopes in such a redirected SETI will have limited use.
Posted by: George Rebane | 18 February 2020 at 01:00 PM
GeorgeR: If nothing else, we have the opportunity to create our own aliens. Not just machine intelligence but perhaps by increasing the communications abilities and general intelligence of other primates and dolphins/whales.
Seeing as how the now-deceased Koko the Gorilla had an estimated IQ of 70-90 and the average for humans in Equatorial Guinea is 59 there's no doubt a lot to yet to be learned about biological intelligence, it's possibly inaccurate measuring, and the importance of built-in social behavior.
Either that, or we should start allowing gorilla immigrants.
Posted by: scenes | 18 February 2020 at 01:36 PM
scenes 136pm - Interesting approach to assuage SETI frustrations, but I don't think it would have the impact of another copernican expansion of our place in the universe.
BTW, I wish you could meet our gran dame Dobie named Puna, now almost 11 years old. In addition to working with the Navy's marine mammal programs, I have a history of making 'super dogs' that have impressed friends and family for decades. I'm told that high-IQ dogs (Dobies along with standard poodles are #2 behind the Australian sheep dog) have the cognitive capacity of a 2-year-old human. Puna is the sixth in that distinguished line. I think I've described my novel method of 'training' dogs somewhere in these pages, but today this is all I could find -
https://rebaneruminations.typepad.com/rebanes_ruminations/2009/08/our-new-puppy.html
Posted by: George Rebane | 18 February 2020 at 03:20 PM