I’m impressed with the number of people posting here who are well-read in SETI and related matters. I’ve just recently begun digging into the subject.
I don’t have much to add, except:
Before we can find life, if it’s out there, we have to come to a consensus as to how we define life. There could be “things” out there that we don’t recognize as being alive. In fact, we could mistake life out there for some sort of non-living natural phenomenon like running water. Heck, even here, we have things that we’re not sure are really alive - viruses, Congress, etc.
Before we can find intelligent life, if it’s out there, we have to come to a consensus as to how we define intelligence. There may be beings out there that consider themselves to have intellect, but in a way we wouldn’t recognize. Here on Earth we face the issue with cetaceans, some birds, Congress, etc.
With all that said, there could be intelligent life (by their definition) that doesn’t recognize us as being intelligent or alive at all. We could find intelligent life and not even recognize it for what it is.
Arguing that civilizations will advance beyond detectable signals kind of ignores the idea that a civilization would leave a radio beacon going for the express purpose of getting in contact with the new planets to come online. Somebody out there might be eager to make contact. Electromagnetism seems like a fair assumption for a common denominator?
Glitch’s post about how slow the conversation would happen is pretty depressing and a really good point. Maybe some civilization will figure out faster than light communication, but we’d currently be missing those signals since we have no receiver.
Finally, I wanted to say that I really disagree with the very end of the video about how the aliens we meet won’t be squishy, and instead they will be some sort of computer people. This assumes that computer technology is somehow the pinnacle of technological achievement and totally ignores biological research and technology. How long until we can create any organic, biological structures or organisms that we dream up? I think we’re going to unlock an awful lot more about how DNA works enabling us to do things with squishy tech that would be silly to try to do with metal tech.
But if you’re persistent enough to keep trying, most extraterrestrial societies eventually find that there’s a shockingly easy way to travel to other UNIVERSES, and then all migrate to a universe right next door where their Star Trek fantasies come true.
I’m also given to the inclination towards machine intelligence.
If you don’t have to teraform anything and individuals can just chill in whatever virtual paradise they like, perhaps the conceptual foundation of life evolves and we’re looking for the wrong imprint.
Although in that case, the simulation question begs being asked and that’s one freaky rabbit-hole to venture near.
You know this is a subject i"ve been facinated by ever since I was able to remember 9well that and dinosaurs… Hmm Alien Dinosaurs.)
Anyway I’m reading the thread and find a whole lot of interesting and feel completely blown out of the water. So about all I can add is ‘What if we really are alone?’ or rather ‘What if WE are the precursor race of the galaxy that latter species would see as the Old Ones of their time?’
Honestly? I just want to be alive not for alien confirmation but just for us going back into space beyond orbiting and giving refills to the ISS.
Electromagnetism, yes, including light. There are one or more OSETI programs - Optical SETI. The thought here is that it’s cheaper, power-wise, to generate light than radio. Astronomers are looking for pulses of infrared laser light in the nanosecond range. There aren’t any (never say never) natural sources of light that pulse for such a short time, and infrared is the best part of the spectrum for punching through interstellar dust and gas (and atmospheres).
What’s interesting overall with SETI is the justification for conducting the searches the way they do. I won’t get into specific numbers and all that, but in an effort to maximize the efficiency of the search some things are being assumed, like the frequency that’s likely to be used for an alien transmission. I’m not saying that they’re wrong - they’ve chosen the most workable options - but that of course leaves many, many other options open that we’re just not able to check, and what we find necessary to pass up may just be what ET has decided to use. Overall though, I’m impressed with the thought process that’s gone into planning the searches.
The more likely it is that a beacon of any sort would work, the even more likely that a race (including us) would think to just send probes that can beam more detailed info back to us (including scientific info, etc.). That’s already part of the scientific path, true?
The further away a system, the less likely a beacon would noticeable, this gets more true when you get to the more ‘fashionable’ regions of the inner galaxy rather than out in the boondocks where we are. Then perhaps we’d think a beacon more focused on the galactic center (everything gradually gets closer together at the very least), but it’s noisier there, so a beacon’s less plausible.
Then you hit the idea of detecting Dyson spheres, which is a sort of backwards beacon, the whole infrared thing SOUNDS good until you realize that we’d never be stupid enough to start a multi-million year grand construction project like that around OUR sun, we’d be far better served finding the nearest red dwarf and using that instead, because some of them will last trillions of years. So. . . least detectable and least interesting stars, ironic, isn’t it?
I’m not finding many scenarios where any spacefaring race would think a beacon was a good idea, including ours.
If I were intending to send a big “Hello!”, I’d arrange for a long-term method of doing it. First thought: big ol’ transmitters, each pointing at a candidate star. Put 'em on satellites in nice stable quiet places like L4, and leave them doing their thing. We could do that now.
The distance between stars is something close to three, four, ten or more light years. Basically, that means that someone travelling with the same speed as light(there is no proof that´s even theoretically possible) would take something close to four years to reach Proxima Centauri, the closest Star System to the Earth.
It´s entirely possible that there is no way, even for the most possible advance civilization, to travel between stars. It´s also entirely possible that life is extremely common in this galaxy and that on the same time, humanity never manages to find, discover or enter contact with them.
It´s also entirely possible that no other stars other than yellow stars can manage to sustain life - if that´s true, only a small number of stars that we know would manage to sustain life. It´s also possible that the humankind never manages to find any yellow star that´s distant more than forty or one hundred light years away.
No one knows, but I would not be so sure about contact with alien life.
Or they just grow up and learn to live happily in their ecological niche, part of a huge and rich totality of life that doesn’t need to destroy everything else around them like a cancer. People like that might become spacefarers through deep understanding of the very bones of reality, but they would still stay as far away from humans as possible, neh?
That really would be the best answer. Then we could fulfil the age old human dream of exploring new life and civilizations, and curb stomping their culture under our imperial hegemony.
Yeah, I think a combination of the two seems terribly likely, doesn’t it? Even if there was some sort of singularity event, we can’t expect some alien culture to all agree when WE never do, right?
Some degree of inherent population control also seems likely. We’re kind of reckless with our baby making (and then most people don’t take terribly good care of them when they’re made). Those are kind of manufactured, cultural issues. . . but individuals don’t generally WANT to make enough little people to overpopulate the world and waste all the stuff, do they?
