My dad launched the quest to find alien intelligence(nationalgeographic.com)
nationalgeographic.com
My dad launched the quest to find alien intelligence
https://www.nationalgeographic.com/science/2020/06/father-launched-quest-find-alien-intelligence-changed-astronomy/
178 comments
Ants aren’t capable of meta cognition though. While I agree the analogy is useful it sort of falls down when you apply it to something else. Like birds or dogs. They clearly know humans exist and how they can be manipulated or contacted. The species difference argument at that level then results in a different conclusion, that yes we can communicate but we are probably not all that interesting. Expanding on this birds and dogs don’t know human motivations. We probably don’t understand how alien aliens are. We can barely understand the motivations of others in our immediate social circle. The question we should ask ourselves then is what motivates aliens and how do we trigger that motivation to initiate contact (carefully).
I think OP chose ants because of the scale involved. Ants form full-fledged civilizations which occupy relatively small volumes of space compared to human civilizations (population size non-withstanding) and even when building around man-made structures, they might not be able to recognize these structures as non-natural.
Yeah it could be a one and/or combination of things. We can’t really know. It’s hard to think of aliens that are so advanced that couldn’t conceptualise us, do they not have fiction? If a species were born post physical or with capabilities that seemed advanced though then I think the ants analogy does apply. Something like space whales in Star Trek to us it’s intergalactic travel to them it’s swimming.
Hot take: Dark matter is space whales.
"Eksperiment" by Janusz A. Zajdel. Polish sci-fi titan equal to Lem of 'Solaris' fame :
https://translate.google.com/translate?hl=en&sl=pl&tl=en&u=h... google translated ebook rip
and similarly themed "He Who Shrank" by Henry Hasse https://en.wikipedia.org/wiki/He_Who_Shrank
https://translate.google.com/translate?hl=en&sl=pl&tl=en&u=h... google translated ebook rip
and similarly themed "He Who Shrank" by Henry Hasse https://en.wikipedia.org/wiki/He_Who_Shrank
Single ants don't have any idea, but anthills as a system probably have some kind of a working model of human activity.
For example ants often feed off garbage cans so they know how the amount of garbage changes daily and weekly. I don't know how good ant systems are at generalizing and noticing patterns but if they are any good they probably know at least that about human civilization.
Do they "think" of humans as another kind of anthill - probably not. But they certainly notice and react to changes in environment caused by human activity.
For example ants often feed off garbage cans so they know how the amount of garbage changes daily and weekly. I don't know how good ant systems are at generalizing and noticing patterns but if they are any good they probably know at least that about human civilization.
Do they "think" of humans as another kind of anthill - probably not. But they certainly notice and react to changes in environment caused by human activity.
The ants have built pretty impressive detectors. Nevermind the humans. Where the heck are all the other anthills? It's quite scary there is only one in a very large detection radius.
The detectors still trying to find the distinctive scent. Which gets lost in all the fumes, dust, whatnot produced by humans...
The silence from SETI is deafening. I'm not even amateurishly familiar with astronomy, but I remember setting up SETI@Home when I got my first computer, and remember slowly realizing that the universe seemingly isn't "teeming" with intelligent life. Maybe something is out there, but out of reach, or deliberately silent? Maybe we are alone in this huge universe?
It does feel at least a little depressing that discovery of extraterrestrial intelligence seems unlikely in my lifetime. Maybe even out of the cards for humanity. I have to wonder if building communications devices (or "devices" in general) is a uniquely human thing that simply wouldn't matter to an intelligence that evolved some other way.
It does feel at least a little depressing that discovery of extraterrestrial intelligence seems unlikely in my lifetime. Maybe even out of the cards for humanity. I have to wonder if building communications devices (or "devices" in general) is a uniquely human thing that simply wouldn't matter to an intelligence that evolved some other way.
It's about signal and noise. Let's say there is a civilization out there, and we know about each other and want to talk. We point a big parabolic antenna at each other and start exchanging radio massages. That's what we are doing with Voyager right now, we point some high-gain antennas at each other and talk. At the rate of 7.2 kb/s [1], or one quarter of the bandwidth of the old dialup connections. But Voyager is close, stars are far. The closest star is about 2000 times farther than Voyager 1. Radio waves decay with the square of the distance, so if a Voyager-size antenna were to transmit towards us from 2000 times farther away, we'd get a signal 4 million times weaker. So, our friends out there need a much bigger antenna than the one on the Voyager, and we need them to point it straight at us, and we need them to blast a mighty strong radio signal towards us. We should also point a bigger antenna at them (the one we point at Voyager is 70 meter wide, not really a toy). Somehow between their bigger antenna and our bigger antenna, we need to overcome the 4 million decay factor. If our friends are 10 times farther away from us than Proxima Centauri, then we need to overcome another factor of 100.
But, our friends out there don't know about us, and they don't set up a mighty large antenna and align it perfectly in our direction. They simply chatter locally using radio waves, in many cases, their antennas are pointing towards their intended receivers, and not randomly towards some exoplanet far far away (the Earth).
SETI never had a chance to find anything.
[1] https://voyager.jpl.nasa.gov/mission/spacecraft/instruments/...
But, our friends out there don't know about us, and they don't set up a mighty large antenna and align it perfectly in our direction. They simply chatter locally using radio waves, in many cases, their antennas are pointing towards their intended receivers, and not randomly towards some exoplanet far far away (the Earth).
SETI never had a chance to find anything.
[1] https://voyager.jpl.nasa.gov/mission/spacecraft/instruments/...
The more significant 'silence' is the fact that every star in the Milky Way galaxy has not already been colonized and turned into a Dyson sphere.
Species with language and toolmaking capabilities seemingly grow in technological sophistication at an exponential rate, so on the geological timescale, will quickly acquire space flight, grow to populations of trillions, harness the resources of their star system, then move onto settling a new star, and so on.
Species with language and toolmaking capabilities seemingly grow in technological sophistication at an exponential rate, so on the geological timescale, will quickly acquire space flight, grow to populations of trillions, harness the resources of their star system, then move onto settling a new star, and so on.
Why do you believe that?
You're making the assumption that the problems involved with prolonged space travel are solvable with the time and resources we have here.
It could not be. It could be too expensive to colonize beyond the immediate area. If even the immediate area can be colonized.
There's also the assumption that there's going to be a good reason to make a non-returnable investment. Because, at some point, that's what it is. The speed of light is a limit we have not even come close to exceeding, much less approaching. And even if we do, and the people on the ship, time dilation, yadda, yadda. It does not matter. The people on Earth will still experience time normally. It taking the ship no time at all does not matter if it takes 1000 years on Earth. Or even 50 years. The return has to be phenomenal or the cost negligible.
You're making the assumption that the problems involved with prolonged space travel are solvable with the time and resources we have here.
It could not be. It could be too expensive to colonize beyond the immediate area. If even the immediate area can be colonized.
There's also the assumption that there's going to be a good reason to make a non-returnable investment. Because, at some point, that's what it is. The speed of light is a limit we have not even come close to exceeding, much less approaching. And even if we do, and the people on the ship, time dilation, yadda, yadda. It does not matter. The people on Earth will still experience time normally. It taking the ship no time at all does not matter if it takes 1000 years on Earth. Or even 50 years. The return has to be phenomenal or the cost negligible.
I assume the cost of settling other stars would become negligible at some point. If our solar system becomes a Dyson Sphere, and we have a population of thousands of trillions of people, I can't imagine how launching laser propulsion spacecraft that can travel at 0.2c toward other stars wouldn't be easily within reach of any moderately wealthy coalition of space enthusiasts.
You're right though. I haven't actually done a careful estimate of the resources required vs the resources available to a Type II civilization. If the former is significant relative to the latter, and there is no Return that can motivate that magnitude of an investment with the type of investment structures that will evolve on a solar-system-wide economy - where investment time horizons have no need to be extraordinarily long - then maybe interstellar colonization is not inevitable.
You're right though. I haven't actually done a careful estimate of the resources required vs the resources available to a Type II civilization. If the former is significant relative to the latter, and there is no Return that can motivate that magnitude of an investment with the type of investment structures that will evolve on a solar-system-wide economy - where investment time horizons have no need to be extraordinarily long - then maybe interstellar colonization is not inevitable.
This is getting close to imagining a perfectly spherical cow in a frictionless environment.
Why do you assume the cost of settling other stars would become negligible?
Our solar system is not a Dyson Sphere. What makes you think it will become one?
We don't have a population of thousands of trillions. Why do you think we'll get there in a manner in which all of them will be coordinated under one banner?
What makes you think that laser propulsion will be practical for such applications? Considering we haven't had a single laser propelled craft used in space exploration. Also, 0.2c is a clever way of not saying 20% the speed of light. Or 100 million miles per hour. How long do you think it will take to get a person to that speed? At 3g, it would take over a month of pure acceleration. The human body can withstand 3g for about an hour. You'd have to accelerate closer to 1g once you've broken Earth orbit. And now you're talking months. Months to accelerate, months to decelerate.
So yes, if we solve all of these other really, really, really, really hard problems, some of the other problems aren't that hard.
Why do you assume the cost of settling other stars would become negligible?
Our solar system is not a Dyson Sphere. What makes you think it will become one?
We don't have a population of thousands of trillions. Why do you think we'll get there in a manner in which all of them will be coordinated under one banner?
What makes you think that laser propulsion will be practical for such applications? Considering we haven't had a single laser propelled craft used in space exploration. Also, 0.2c is a clever way of not saying 20% the speed of light. Or 100 million miles per hour. How long do you think it will take to get a person to that speed? At 3g, it would take over a month of pure acceleration. The human body can withstand 3g for about an hour. You'd have to accelerate closer to 1g once you've broken Earth orbit. And now you're talking months. Months to accelerate, months to decelerate.
So yes, if we solve all of these other really, really, really, really hard problems, some of the other problems aren't that hard.
>>Our solar system is not a Dyson Sphere. What makes you think it will become one?
Because 1. of the accelerating rate of technological progress that we've seen over the last 2 million years, and 2. the deduction that preferential selection leads to economic systems that harness more energy and replicate themselves becoming more common
>>We don't have a population of thousands of trillions. Why do you think we'll get there in a manner in which all of them will be coordinated under one banner?
They wouldn't need to all be under one banner.
>>What makes you think that laser propulsion will be practical for such applications?
Because we understand the physics of it. It's theoretically possible, and assuming sufficient advances in science and engineering, will become practically possible.
>>And now you're talking months. Months to accelerate, months to decelerate.
I don't see such a requirement preventing interstellar colonization.
Because 1. of the accelerating rate of technological progress that we've seen over the last 2 million years, and 2. the deduction that preferential selection leads to economic systems that harness more energy and replicate themselves becoming more common
>>We don't have a population of thousands of trillions. Why do you think we'll get there in a manner in which all of them will be coordinated under one banner?
They wouldn't need to all be under one banner.
>>What makes you think that laser propulsion will be practical for such applications?
Because we understand the physics of it. It's theoretically possible, and assuming sufficient advances in science and engineering, will become practically possible.
>>And now you're talking months. Months to accelerate, months to decelerate.
I don't see such a requirement preventing interstellar colonization.
> Because 1. of the accelerating rate of technological progress that we've seen over the last 2 million years, and 2. the deduction that preferential selection leads to economic systems that harness more energy and replicate themselves becoming more common
So, in other words, no clue, just wishing. You've seen a logarithmic rise and don't even consider that it could level off in the same fashion. The graph of technological advancement could be an arctan.
> They wouldn't need to all be under one banner.
So everyone handles their part of the sphere? And how do we decide where to go once we get it moving?
> Because we understand the physics of it. It's theoretically possible, and assuming sufficient advances in science and engineering, will become practically possible.
In theory, there is little difference between theory and practice, in practice there is a hell of a lot of difference.
Also, I'm not granting your assumptions. Why do you believe those assumptions? You've not given a reason besides that you believe that we will continue progressing at an exponential rate.
> I don't see such a requirement preventing interstellar colonization.
Then you don't understand the problems.
So, in other words, no clue, just wishing. You've seen a logarithmic rise and don't even consider that it could level off in the same fashion. The graph of technological advancement could be an arctan.
> They wouldn't need to all be under one banner.
So everyone handles their part of the sphere? And how do we decide where to go once we get it moving?
> Because we understand the physics of it. It's theoretically possible, and assuming sufficient advances in science and engineering, will become practically possible.
In theory, there is little difference between theory and practice, in practice there is a hell of a lot of difference.
Also, I'm not granting your assumptions. Why do you believe those assumptions? You've not given a reason besides that you believe that we will continue progressing at an exponential rate.
> I don't see such a requirement preventing interstellar colonization.
Then you don't understand the problems.
>>So, in other words, no clue, just wishing. You've seen a logarithmic rise and don't even consider that it could level off in the same fashion.
The logarithmic rise has been in place for a long time. The likelihood that it ends in the near future, before long-range space flight, seems unlikely.
This is especially so because the resources and capabilities being unlocked by new innovations seem to be inherently expand human civilization's rate of innovation.
For example, the cutting edge of technology today, like reusable rockets, NN-based machine-learning, and 3D printing, seem very likely to exponentially increase the resources/productive-output of our civilization.
Intuitively, I don't see any reason this accelerating progress will stop until physical laws become the only major limiting factor, and these laws allow for an exponentially expanding, seafaring civilization.
Of course, I don't know for certain. It goes without saying that these sorts of discussions are speculative.
>>So everyone handles their part of the sphere? And how do we decide where to go once we get it moving?
We don't need to propel the entire Dyson Sphere. Some group(s) needs to create a massive laser emitter, and use it to propel an artificial craft.
>>In theory, there is little difference between theory and practice, in practice there is a hell of a lot of difference.
Theory tells us what is possible. History tells us what to expect in terms of long term trends.
Based on the longstanding trend and intuitions about the nature of technological/economic evolution, I think we can expect anything that is theoretically possible to do with a small fraction of the resources extractable by a Type II civilization, will be done by human civilization, and hence interstellar colonization will be possible.
The logarithmic rise has been in place for a long time. The likelihood that it ends in the near future, before long-range space flight, seems unlikely.
This is especially so because the resources and capabilities being unlocked by new innovations seem to be inherently expand human civilization's rate of innovation.
For example, the cutting edge of technology today, like reusable rockets, NN-based machine-learning, and 3D printing, seem very likely to exponentially increase the resources/productive-output of our civilization.
Intuitively, I don't see any reason this accelerating progress will stop until physical laws become the only major limiting factor, and these laws allow for an exponentially expanding, seafaring civilization.
Of course, I don't know for certain. It goes without saying that these sorts of discussions are speculative.
>>So everyone handles their part of the sphere? And how do we decide where to go once we get it moving?
We don't need to propel the entire Dyson Sphere. Some group(s) needs to create a massive laser emitter, and use it to propel an artificial craft.
>>In theory, there is little difference between theory and practice, in practice there is a hell of a lot of difference.
Theory tells us what is possible. History tells us what to expect in terms of long term trends.
Based on the longstanding trend and intuitions about the nature of technological/economic evolution, I think we can expect anything that is theoretically possible to do with a small fraction of the resources extractable by a Type II civilization, will be done by human civilization, and hence interstellar colonization will be possible.
Yes, I agree. Just note, that this is assuming however, that no alien civilization has developed any vessels that would bring them closer to use, e.g. in our solar system so we could detect their signals
Even the focus on on radio is potentially misguided. Perhaps there are alien species who's home planet is under some heavy fog so they have evolved to see the reflection of radio waves, to then go bouncing high power radio signals around could potentially blind themselves so they have evolved some other means of distant communications.
That's just one failure scenario, if you took a Wifi signal and could somehow transport it back in time 100 years and blast it out at 1000 times the normal energy how long would it take past us to notice?
That's just one failure scenario, if you took a Wifi signal and could somehow transport it back in time 100 years and blast it out at 1000 times the normal energy how long would it take past us to notice?
I think even 100 years ago, a kilowatt microwave transmitter would probably draw attention to itself by the way that eggs explode and cups of water boil when near it.
Fair point. Call it 60w or even 1w if that feels better. It's still many orders of magnitude over what you would be receiving across space from another solar system.
Also, for mild amusement, your comment reminded me of this video https://www.youtube.com/watch?v=b9UO9tn4MpI
Also, for mild amusement, your comment reminded me of this video https://www.youtube.com/watch?v=b9UO9tn4MpI
You would have to stand right next to a 1kw microwave transmitter to notice any heating effects. That wouldn't help you locate it at any distance.
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The SETI Institute has a very active YouTube channel if you are interested in updates: https://www.youtube.com/channel/UCzQdkHKOTVT_chwgDcau4sg
They also provide publicly available audit for their financials so you can see where they are at: https://www.seti.org/about-us/financials
As far as I can tell, they are still going strong. And the YouTube channel is always very interesting, and cutting-edge! It's not always about alien life directly, many times it is tangentially related (helpful [to the search] technologies, breakthroughs, panel discussions, etc). Perhaps not the most refined broadcasts, but they are always very educational and informative.
They also provide publicly available audit for their financials so you can see where they are at: https://www.seti.org/about-us/financials
As far as I can tell, they are still going strong. And the YouTube channel is always very interesting, and cutting-edge! It's not always about alien life directly, many times it is tangentially related (helpful [to the search] technologies, breakthroughs, panel discussions, etc). Perhaps not the most refined broadcasts, but they are always very educational and informative.
We are the only animal species capable of sending radio waves in space. For all we know it's an accident. Dinosaurs or scorpions lived longer than us as species but would probably never reach that level.
So the universe may well be teeming with life, but not the kind that sends radio waves.
So the universe may well be teeming with life, but not the kind that sends radio waves.
We have only covered ~200ly with radio waves. That is a small spot in our galaxy, let alone universe. The core is ~25.000ly away. I think the original signal would be highly distorted by then. I still think seti@home was worth it, but it cannot answer the question about alien life negatively if it doesn't net a positive result.
True. I have always wondered why no other species on Earth have evolved in a way Humans have. Every other species maintains the balance in nature but we are the only species actively creating imbalance and destroying the planet. Prometheus might have been true after all.
All the species evolve the same way.
None of the species care about any specific "balance".
Humans are not destroying the planet (talk about hubris), but the biosphere and possibly the civilization.
None of the species care about any specific "balance".
Humans are not destroying the planet (talk about hubris), but the biosphere and possibly the civilization.
I don't know about that. One species poisoned most other to death, a long time ago.
What species might that be?
There are five known big mass extinction events in Earth life history, the first one is caused by... drumroll... small plants.
https://www.youtube.com/watch?v=mAkjETPM1s4
That lead me to this one, he's funny: https://www.youtube.com/watch?v=FlUes_NPa6M
That's because sooner or later every species enters an equilibrium state with the amount of energy available in the ecosystem. In the process it may out-compete quite a bit of other species, and so we speak of 'invasive species'.
> Maybe something is out there, but out of reach, or deliberately silent?
Have you read The Three Body Problem series by Cixin Liu? It's a terrific (and recently quite famous + awarded) sci fi trilogy that explores this idea. That all sufficiently advanced civilizations have learned to be extremely radio silent in order to escape detection. Reason being that they all eventually conclude that, from a game theoretic standpoint, the only reasonable thing to do when you detect another civilization is to eliminate them before they do you.
Have you read The Three Body Problem series by Cixin Liu? It's a terrific (and recently quite famous + awarded) sci fi trilogy that explores this idea. That all sufficiently advanced civilizations have learned to be extremely radio silent in order to escape detection. Reason being that they all eventually conclude that, from a game theoretic standpoint, the only reasonable thing to do when you detect another civilization is to eliminate them before they do you.
The problem I see with this idea is that it depends on either FTL travel, or on a horizon of time much larger than I would imagine. If we were discovered by a war-like civilization in one of the nearer stars today, it may well take them hundreds or thousanfs of years to get here even with a probe. Is it really a plausible threat?
When malicious eavesdroppers are involved, some fates are worse than death...
http://freefall.purrsia.com/ff400/fv00307.htm#anunsecuredlin...
Others like Vernor Vinge have speculated that the galactic net has really bad malware.
http://freefall.purrsia.com/ff400/fv00307.htm#anunsecuredlin...
Others like Vernor Vinge have speculated that the galactic net has really bad malware.
This assumes that alien civilizations purely see us as competition and not an organism they can achieve synergy with.
What if organisms could choose other ways of allying and joining together? What if, say, you had the strong, dominant, ambitious sub-population of a race trying to ally with other strong, dominant, ambitious life forms without thought to race? What if the organisms in the universe which favored peace decided to seek each other out and unite for a common cause?
What if organisms could choose other ways of allying and joining together? What if, say, you had the strong, dominant, ambitious sub-population of a race trying to ally with other strong, dominant, ambitious life forms without thought to race? What if the organisms in the universe which favored peace decided to seek each other out and unite for a common cause?
> What if organisms could choose other ways of allying and joining together? What if, say, you had the strong, dominant, ambitious sub-population of a race trying to ally with other strong, dominant, ambitious life forms without thought to race? What if the organisms in the universe which favored peace decided to seek each other out and unite for a common cause?
That could be true.
Judging by history, that's not a very good bet. Peace sort of works among humans, in part because we are so close genetically. But Pre-WWI Europe showed that you can't engineer peace even by inter-marrying rulers.
Stepping away from humans a small amount, even today people regularly eat primates of various sorts (i.e. "bush meat").
Why do you think humans would ever make peace with alien cultures?
That could be true.
Judging by history, that's not a very good bet. Peace sort of works among humans, in part because we are so close genetically. But Pre-WWI Europe showed that you can't engineer peace even by inter-marrying rulers.
Stepping away from humans a small amount, even today people regularly eat primates of various sorts (i.e. "bush meat").
Why do you think humans would ever make peace with alien cultures?
> Why do you think humans would ever make peace with alien cultures?
Great question. Maybe we need interstellar mutually-assured destruction. Seems to be the only thing, short of dominance, that has worked to preserve peace(-ish).
Great question. Maybe we need interstellar mutually-assured destruction. Seems to be the only thing, short of dominance, that has worked to preserve peace(-ish).
> Maybe we need interstellar mutually-assured destruction. Seems to be the only thing, short of dominance, that has worked to preserve peace(-ish).
It seems unlikely to me that when 2 alien cultures meet, that their technology levels are so similar that MAD is possible.
It seems unlikely to me that when 2 alien cultures meet, that their technology levels are so similar that MAD is possible.
It might not need to be about technology, but biology, à la War Of The Worlds.
Whilst I doubt that (all of?) our viruses would have any effect on them (as they require our own cells to reproduce - aliens are unlikely to have a similar makeup), but things like funguses and bacteria could be very very bad for them.
Whilst I doubt that (all of?) our viruses would have any effect on them (as they require our own cells to reproduce - aliens are unlikely to have a similar makeup), but things like funguses and bacteria could be very very bad for them.
Seems fairly unlikely though.
Random bacteria and fungii that are introduced to humans don't kill us all off. Bacteria especially are everywhere, it stands to reason that over all of the exploring, investigating and just plain spreading that we do, we'd encounter some bacteria that are new to a population. If those had any great chance of killing us off, shouldn't at least local examples exist of that happening?
Instead I think what we see are the organisms that affect us are those that coevolve with either us or with related species. We're killed by the things we spend a lot of time with, not random out-of-context bacteria that's never seen a mammal before.
If that's true of us, seems hard to say why it wouldn't be true of aliens, no?
Random bacteria and fungii that are introduced to humans don't kill us all off. Bacteria especially are everywhere, it stands to reason that over all of the exploring, investigating and just plain spreading that we do, we'd encounter some bacteria that are new to a population. If those had any great chance of killing us off, shouldn't at least local examples exist of that happening?
Instead I think what we see are the organisms that affect us are those that coevolve with either us or with related species. We're killed by the things we spend a lot of time with, not random out-of-context bacteria that's never seen a mammal before.
If that's true of us, seems hard to say why it wouldn't be true of aliens, no?
> We're killed by the things we spend a lot of time with, not random out-of-context bacteria that's never seen a mammal before.
We're mostly killed by things that have never been in humans before because we haven't developed defenses. Sure, most of those things don't kill us, but you really only need the right one to come along and basically wipe us out. Part of the reasons we're ultimately able to develop a defense is because it is Earth life and we've seen all the tricks. Any alien microbe that is able to establish itself inside our bodies might not have to worry about any of our defenses.
I think you've really got the wrong model. Think of the introduction of non-native species to various ecosystems. A lot of the time, the non-native species either can't hack it, or they find an equilibrium. But some of the time you get kudzu or eurasian watermilfoil.
In any case, the point is largely moot. Any civilization we are likely to meet in the next thousands of years will necessarily have to visit us and if they can do that, they can just lob a couple space rocks at Earth and wipe us out from a distance.
We're mostly killed by things that have never been in humans before because we haven't developed defenses. Sure, most of those things don't kill us, but you really only need the right one to come along and basically wipe us out. Part of the reasons we're ultimately able to develop a defense is because it is Earth life and we've seen all the tricks. Any alien microbe that is able to establish itself inside our bodies might not have to worry about any of our defenses.
I think you've really got the wrong model. Think of the introduction of non-native species to various ecosystems. A lot of the time, the non-native species either can't hack it, or they find an equilibrium. But some of the time you get kudzu or eurasian watermilfoil.
In any case, the point is largely moot. Any civilization we are likely to meet in the next thousands of years will necessarily have to visit us and if they can do that, they can just lob a couple space rocks at Earth and wipe us out from a distance.
> it stands to reason that over all of the exploring, investigating and just plain spreading that we do, we'd encounter some bacteria that are new to a population. If those had any great chance of killing us off, shouldn't at least local examples exist of that happening?
We have examples of exactly this! It was very bad: https://en.wikipedia.org/wiki/Native_American_disease_and_ep...
We have examples of exactly this! It was very bad: https://en.wikipedia.org/wiki/Native_American_disease_and_ep...
Those were diseases already in humans moving to an untouched population of humans, not what I was talking about.
A bacterium that hasn't seem humans before is pretty unlikely to be able to do anything to us. One that hasn't even been in mammals before is even less likely, etc.
A bacterium that hasn't seem humans before is pretty unlikely to be able to do anything to us. One that hasn't even been in mammals before is even less likely, etc.
They definitely could choose. The problem is: communication. Light speed, although fast, isn't fast enough for communication between vast distances. How can you establish any sort of trust when messages take decades/centuries to deliver? It'd simply be safest to expect the worst.
this is where i lost interest in the book. the idea that
destroying another civilization is the only reasonable choice is beyond ridiculous.
first of all, game theory is based on our current experience and conditioning. if we raise a society where cooperation is valued, then the outcomes of game theory will change too. it is absurd to assume that game theory is universal.
but even if it were, and we'd have to assume that all aliens are hostile, the recources necessary to mount an expedition to another inhabited solar system are much larger than the benefits of exploiting a remote planet. it's simply not worth it.
what would be the point?
my expectation is that before we are able to send ships we'll be communicating for a long period, giving us enough time to share scientific discoveries.
i'll even go as far as to claim that developing space travel that can take us to another inhabited solar system will only happen in collaboration with the civilization that we want to visit.
first of all, game theory is based on our current experience and conditioning. if we raise a society where cooperation is valued, then the outcomes of game theory will change too. it is absurd to assume that game theory is universal.
but even if it were, and we'd have to assume that all aliens are hostile, the recources necessary to mount an expedition to another inhabited solar system are much larger than the benefits of exploiting a remote planet. it's simply not worth it.
what would be the point?
my expectation is that before we are able to send ships we'll be communicating for a long period, giving us enough time to share scientific discoveries.
i'll even go as far as to claim that developing space travel that can take us to another inhabited solar system will only happen in collaboration with the civilization that we want to visit.
Probably in universe time, equivalent intelligent civilizations will only be using radio waves for communication for maybe few hundred years. To be able to find radio signal from another civ in that window of time is unlikely. A more advanced Comm method is used.
In this series they move on to gravitational waves.
I have not, I will definitely check that out, thanks for sharing. I feel that SETI is something I'm woefully uneducated on, and can't find good places to jump into research before sources seem to go wildly off the rails.
Yeah I can testify that it's one of the best Sci-Fi novels these years. I read the original Chinese version but I heard that the translation of 1st and 3rd book (by same person) is excellent.
Wouldn't someone send communication signals to lure or bait other civilizations? For example, spam a friendly hello message on every potential communication channel and encourage new civilizations to reply. When they do, destroy them.
No, because that'd just be endangering your own civilization unnecessarily. There's always a bigger, badder civ out there :)
But earth debunks that theory, no body came to destroy us yet.
We can't send a strong enough radio signal to be detectable at any other nearby stars
The Three Body Problem is great, but it assumes the existence of weapons of ludicrous destructive power.. The only other time I've ever seen a piece of fiction where someone had that amount of destructive power was in a cartoon. (And even then I only saw it once)
If you assume that there's no faster-than-light space travel, it doesn't really make any sense to engage in interstellar conflict IMO. The same tech that would let you travel between the stars would also let you live in comfortable artificial habitats around your own home star, close enough to the rest of your civilization to be able to watch TV and keep up with HackerNews.
The Three Body Problem is great, but it assumes the existence of weapons of ludicrous destructive power.. The only other time I've ever seen a piece of fiction where someone had that amount of destructive power was in a cartoon. (And even then I only saw it once)
If you assume that there's no faster-than-light space travel, it doesn't really make any sense to engage in interstellar conflict IMO. The same tech that would let you travel between the stars would also let you live in comfortable artificial habitats around your own home star, close enough to the rest of your civilization to be able to watch TV and keep up with HackerNews.
> The Three Body Problem is great, but it assumes the existence of weapons of ludicrous destructive power.. The only other time I've ever seen a piece of fiction where someone had that amount of destructive power was in a cartoon. (And even then I only saw it once)
That part doesn't seem to hard to me. A robotic spacecraft could install solar sales on a comet in such a way as to crash it into the target planet a few hundred years later. This could go unnoticed until it was too late by the target planet. Alternatively, a beam-powered probe (e.g. 'starwisp' or similar) moving at relativistic speeds could be crashed into the target planet.
Neither of these require cartoon physics.
That part doesn't seem to hard to me. A robotic spacecraft could install solar sales on a comet in such a way as to crash it into the target planet a few hundred years later. This could go unnoticed until it was too late by the target planet. Alternatively, a beam-powered probe (e.g. 'starwisp' or similar) moving at relativistic speeds could be crashed into the target planet.
Neither of these require cartoon physics.
how detectable would the EMP from nuclear explosions be? Obviously that is strong, but not very directed..
You do realize that there is gigantic nuclear reactor sitting about 93 million miles from where you are right now, right? An energy source so massive, it would only take a small fraction of it to heat and power several full planets. It would be like billions of nuclear explosions every second.
The Sun dwarfs anything we can do on Earth. Any arbitrary explosion of that sort wouldn't even register as noise next to the Sun. Our radio transmissions are directed and deliberate in a way that is noticeable even among the noise. Like watching scrambled HBO on an old cable box.
The Sun dwarfs anything we can do on Earth. Any arbitrary explosion of that sort wouldn't even register as noise next to the Sun. Our radio transmissions are directed and deliberate in a way that is noticeable even among the noise. Like watching scrambled HBO on an old cable box.
Yes. However I don't know if that is different. That is a roaring fire, whereas the https://en.wikipedia.org/wiki/Tsar_Bomba was a 58 megaton event which would have created a pulse. Electronic devices can sit in the sunshine all day, exposed to the roaring fire of the sun but a singular EMP can take them out? When you look for things, you look for what is different to its surroundings. Even when our own people are looking for planets around other stars, they are looking for an incredibly small change. They found something nearly 30,000 light years away like that.
Yes, we're close enough to Earth that it has a lot more affect on us than the Sun. And the Earth has a magnetic shield. Etc.
The Tsar Bomba did not destroy all life on the planet, did it? A simple solar flare is 5 to 10 magnitudes larger. Yes, small changes, but small changes that don't belong.
We are close enough to the Sun that even if that were detectable at the scale of the cosmos, the distance between the Earth and the Sun is a rounding error at the scales we are talking about.
Appreciate this. We are effectively in the Sun's atmosphere. The entire solar system is. Scale matters.
The Tsar Bomba did not destroy all life on the planet, did it? A simple solar flare is 5 to 10 magnitudes larger. Yes, small changes, but small changes that don't belong.
We are close enough to the Sun that even if that were detectable at the scale of the cosmos, the distance between the Earth and the Sun is a rounding error at the scales we are talking about.
Appreciate this. We are effectively in the Sun's atmosphere. The entire solar system is. Scale matters.
Maybe they're still on the way. We didn't start radio broadcasts until quite recently ago.
As other commenters have covered, SETI makes a whole lot of assumptions about what extraterrestrial contact would look like and wastes time exploring the hypothesis that another civilization would behave just like us in our infancy, except at a time when they have the capability and surplus energy to transmit signals many orders of magnitude stronger than we do.
To my knowledge, we are not currently transmitting sustained signals that would be detectable through the noise by any neighboring systems, and to do so for any sustained period of time, let alone a significant enough amount of time to be noticed (geological time scale) AND then wait for a response would take a ridiculous amount of energy, and provide no return on investment for literally thousands of generations. And even then, that return on investment might just be an invasion.
So in my opinion, SETI is a poor use of compute and investigating the more credible of the tens of thousands of as-of-yet unexplained UFO reports would be a better use of time. Either they are already here, or we will not have the tools to discover neighbors (if they exist) until our technology is far more advanced.
To my knowledge, we are not currently transmitting sustained signals that would be detectable through the noise by any neighboring systems, and to do so for any sustained period of time, let alone a significant enough amount of time to be noticed (geological time scale) AND then wait for a response would take a ridiculous amount of energy, and provide no return on investment for literally thousands of generations. And even then, that return on investment might just be an invasion.
So in my opinion, SETI is a poor use of compute and investigating the more credible of the tens of thousands of as-of-yet unexplained UFO reports would be a better use of time. Either they are already here, or we will not have the tools to discover neighbors (if they exist) until our technology is far more advanced.
Carl Sagan has a nice example for this: " we take a glass of water from ocean and assuming there is no fish exist"
Is it possible that the universe is teeming with intelligent life, just randomly distributed throughout cosmic timelines and therefore unlikely to be detected?
It's the possible that every single star has a civilization at the level of our's, actively transmitting and detecting, yet find nothing. IE, Earth couldn't detect the signal of Earth if they were transmitted from the nearest star.
This is seldom mentioned in the press. I learned it here, on hackernews a decade ago, I think. I was shocked. It's shame you get people not knowing basic stuff like this.
This is seldom mentioned in the press. I learned it here, on hackernews a decade ago, I think. I was shocked. It's shame you get people not knowing basic stuff like this.
> The Arecibo Observatory and FAST could each detect the TV carrier wave leakage out to a distance of about sixteen lightyears. That’s a little bit further away than Tau Ceti is.
https://www.forbes.com/sites/quora/2017/01/27/how-far-into-s...
That's for detecting a TV broadcast. But how far away could one Arecibo observatory detect another Arecibo?
> The answer is, that except for obscuration and dust in certain places, it could be anywhere in the galaxy and we would pick up the signals. That means at least one hundred billion stars that you can listen to for signs of extraterrestrial intelligence.
https://www.rollingstone.com/culture/culture-news/carl-sagan...
https://www.forbes.com/sites/quora/2017/01/27/how-far-into-s...
That's for detecting a TV broadcast. But how far away could one Arecibo observatory detect another Arecibo?
> The answer is, that except for obscuration and dust in certain places, it could be anywhere in the galaxy and we would pick up the signals. That means at least one hundred billion stars that you can listen to for signs of extraterrestrial intelligence.
https://www.rollingstone.com/culture/culture-news/carl-sagan...
How far away can our own technologies detect our own transmissions? If a planet 100 light years away was making as much RF noise as us, could we detect it? I thought we could.
One easy way to think about this is:
If our radio signals would make it to a planet 100 light-years away (even if you ignore Inverse-square law), you could probably power them down and still reach all of earth. Why would one pay for that extra, unneeded, power?
If our radio signals would make it to a planet 100 light-years away (even if you ignore Inverse-square law), you could probably power them down and still reach all of earth. Why would one pay for that extra, unneeded, power?
Because antenna gain is a function of both the transmitter and receiver, and detection is different from getting a high-quality signal. Most high-power radio signals on earth are aimed at transmitting to fairly low power, small, cheap devices which need to recover a good amount of information from the signal. This is very different from the requirements of a radio telescope (which has a gain many orders of magnitude higher because it has a much larger space, power, and cost budget) detecting a signal (which requires far lower signal-to-noise than reconstructing something high quality from it).
Our own people on this mote have only been teeming with radio communications for but a blip of time (in the grand scheme of things).
Perhaps we will disappear only to be a part of the fossil record in just as short a blip.
If all radio-species come and go so briefly, consider a signal from another planet serendipitous.
But, you know, you have to try.
Perhaps we will disappear only to be a part of the fossil record in just as short a blip.
If all radio-species come and go so briefly, consider a signal from another planet serendipitous.
But, you know, you have to try.
Except, not even
If an earth-like society existed on the nearest star, transmitting as we do. Neither society could detect the other.
Ideas that we could find stuff that is "out there" presuppose societies that are more advanced, and more advanced on our terms, transmitting as we do but loud enough to "hear".
PLUS what you mention, we in our current incarnation have existed as a blip.
If an earth-like society existed on the nearest star, transmitting as we do. Neither society could detect the other.
Ideas that we could find stuff that is "out there" presuppose societies that are more advanced, and more advanced on our terms, transmitting as we do but loud enough to "hear".
PLUS what you mention, we in our current incarnation have existed as a blip.
> Except, not even if an earth-like society existed on the nearest star, transmitting as we do. Neither society could detect the other.
Proxima Centauri, the nearest star, is 1.301 parsec away (4.25 light years), so sufficient time for a signal to travel between them and us, no?
Maybe you are saying we couldn't detect each other due to a linguistic or intelligence gap?
Proxima Centauri, the nearest star, is 1.301 parsec away (4.25 light years), so sufficient time for a signal to travel between them and us, no?
Maybe you are saying we couldn't detect each other due to a linguistic or intelligence gap?
It presupposes they use radio and that they’re specifically sending a message to us. We have the technological capacity to send such a message. Listening is much cheaper and safer so most civilizations would probably opt to listen.
There is a glimmer of hope!
https://en.wikipedia.org/wiki/Wow!_signal
https://en.wikipedia.org/wiki/Wow!_signal
Last I checked the wow signal was proven to come from microwave interferrence.
Source?
The first SETI-specific NASA grant in over three decades was just awarded so there is still hope we will see something in our lifetime.
https://www.cfa.harvard.edu/news/2020-12
https://www.cfa.harvard.edu/news/2020-12
Space is enormous! While our capacity to search it for signs of intelligence is miniscule.
Dark Forest.
Let's hope we do not contact anything until we have really, really good weapons.
Let's hope we do not contact anything until we have really, really good weapons.
Its a novel.
and it's probably the best hypothesis why we don't seem to find much.
What hypothesis?
SETI never made much sense as a means to find aliens. As a means to get funding and interest in radioastronomy, by spinning more than a bit on the chances of it ever working, it made a lot of sense.
A radio signal could be either intentional or unintentional. An unintentional signal being found is extremely unlikely. Radio isn't very useful for interplanetary communication, so the purpose must be local. But every civilization would have the desire to conserve energy, and it takes a very little time (compared to galaxy-scale distances) to improve it to the point it's very weak. Humanity switched very quickly from weak radio signals (because the power sources were weak) to very weak radio signals (because we knew better what we were doing) to digital. That's a very short time frame and a weak signal. Not likely to be detected.
As for an intentional signal, well, if a powerful enough alien wants to be noticed, it will be. One could always come up with weird scenarios ("they want to test us so they're intentionally sending weak signals") but that's a very double edged sword ("they want to test us to see if they need to exterminate us") which doesn't justify SETI.
A radio signal could be either intentional or unintentional. An unintentional signal being found is extremely unlikely. Radio isn't very useful for interplanetary communication, so the purpose must be local. But every civilization would have the desire to conserve energy, and it takes a very little time (compared to galaxy-scale distances) to improve it to the point it's very weak. Humanity switched very quickly from weak radio signals (because the power sources were weak) to very weak radio signals (because we knew better what we were doing) to digital. That's a very short time frame and a weak signal. Not likely to be detected.
As for an intentional signal, well, if a powerful enough alien wants to be noticed, it will be. One could always come up with weird scenarios ("they want to test us so they're intentionally sending weak signals") but that's a very double edged sword ("they want to test us to see if they need to exterminate us") which doesn't justify SETI.
> As a means to get funding and interest in radioastronomy, by spinning more than a bit on the chances of it ever working, it made a lot of sense.
This sent me looking for the total half-century $ cost of SETI, but couldn't find it. Have any idea if that's been calculated?
This sent me looking for the total half-century $ cost of SETI, but couldn't find it. Have any idea if that's been calculated?
[deleted]
I didn't find much, but I have an idea for calculation:
* Most of their projects have a relatively static cost[0] year-by-year.
* The big variable is SETI@home. From the SETI PoV it's zero-cost, but that's not the case for society (compute, electricity, pollution).
It's not difficult to find TFLOPS estimates via BOINC or wiki. Translating that back to cost is rather difficult, for me at least. Most people did not buy computers for this. Network bandwidth cost is also difficult to estimate. I suspect main component is power for processing. But electricity estimates vary widely depending on hardware used, I dunno how to estimate the average consumption per TLOPS.
[0] https://www.quora.com/What-is-the-annual-cost-of-operating-S...
* Most of their projects have a relatively static cost[0] year-by-year.
* The big variable is SETI@home. From the SETI PoV it's zero-cost, but that's not the case for society (compute, electricity, pollution).
It's not difficult to find TFLOPS estimates via BOINC or wiki. Translating that back to cost is rather difficult, for me at least. Most people did not buy computers for this. Network bandwidth cost is also difficult to estimate. I suspect main component is power for processing. But electricity estimates vary widely depending on hardware used, I dunno how to estimate the average consumption per TLOPS.
[0] https://www.quora.com/What-is-the-annual-cost-of-operating-S...
Dr. Drake is especially famous for the Drake Equation (as the article mentions) which is a fascinating way to think about how many intelligent civilizations might be findable.
https://exoplanets.nasa.gov/news/1350/are-we-alone-in-the-un...
https://exoplanets.nasa.gov/news/1350/are-we-alone-in-the-un...
I’ve heard that the Drake equation was originally (?) intended to be a parable that makes you think about whether our civilization is likely to destroy itself before making a noticeable impact on the universe, in order to promote nuclear disarmament
I’ve studied this a lot but it’s been awhile. Drake et al we’re doing this during the Cold War and were definitely aware we could wipe ourselves out either with weapons or through ecological disaster. The L term is specifically about civilizations destroying themselves (although it can also be advances in technology which end radio-as-we-know-it).
The great filter is an attempt to explain the Fermi Paradox. Fermi was there, but the paradox necessarily came after the Drake equation.
The great filter is an attempt to explain the Fermi Paradox. Fermi was there, but the paradox necessarily came after the Drake equation.
I would bet a million dollars that there are no other intelligent civilizations in the universe.
I would take that bet. The observable universe is estimated to have 10^21 stars and the actual universe is infinite.
The size of the actual universe is irrelevant for this discussion since anything outside the observable universe does not have any casual connection to us.
But of course you are right about the absolutely staggering number of stars in the observable universe.
But of course you are right about the absolutely staggering number of stars in the observable universe.
>The size of the actual universe is irrelevant for this discussion since anything outside the observable universe does not have any casual connection to us.
I don't see how causality plays into the question at hand. The parent post didn't bet that we could interact with alien life, but if it exists at all. If it can be demonstrated that the actual universe is infinite, it will follow that alien live exist, independent of if we can interact with it.
I don't see how causality plays into the question at hand. The parent post didn't bet that we could interact with alien life, but if it exists at all. If it can be demonstrated that the actual universe is infinite, it will follow that alien live exist, independent of if we can interact with it.
This is logically incorrect. The universe may well be infinite, but that doesn’t imply it must harbour life
I believe this would be correct if there were no examples of life already extant - but the fact that we exist shows that the probability of life and civilization arising is strictly greater than 0. Given an infinite universe with a flat probability distribution (i.e. there's nothing particularly special about our little corner), any >0 probability will occur an infinite number of times.
I highly doubt the actual universe is really infinite, however. Incomprehensibly big, yes.
I highly doubt the actual universe is really infinite, however. Incomprehensibly big, yes.
Not enough proof to win the bet, so right now you're losing.
Right now, nobody has proof. While aliens can be discovered at a future date, you can never prove that they don’t exist. It is a very safe bet because they can not prove a negative.
I'm not sure what you mean by the "actual universe" but there's no proof that space is infinite. Unfathomably vast yes, but still finite.
by actual universe, I meant total universe ( opposed to the observable universe). All of the evidence we have collected so far suggests that the universe is flat and infinite. While some finite universes could be proven, so far we have not.
what's the proof it's finite?
Our senses are finite; we cannot directly know infinity through them. Because of that, I think the burden of proof is on the claim that it is infinite.
Why take a bet on something that can never be verified?
Can you unpack your reasoning here? The likelihood of civilizations occurring/existing in parallel leads me to a similar conclusion.
Not OP, but I fully agree with them. Incoming ballpark figures I and hand waving. If, today, with our current technology, we decided to explore/colonize every star and planet in our galaxy, launching 3 ships per day that travel at single digits percent of c, we could investigate every planet in our galaxy in about a billion years. That's pretty much worse case technological scenario, because at some point in the next thousand or million years we'll have even more incredible technology to build more and fly faster. Probes that can constantly accelerate at 1g will reach other galaxies on the order of millions of years. If they self replicate, or have pioneers that can rebuild civilization on the order of a few thousand years and continue exploring, we're still within that 1 billion year limit to colonize at worst the entire galaxy, and realistically the entire universe. Earth has been around for 5 billion years, and the greater universe for 15. Humans have only existed for 10,000 years. ET should have been here long before we even came into existence.
We only have a few thousand years of reliable history and in many places, far less than that. It's perfectly reasonable in your scenario that ET was here long before we were, missed us by a couple of million years and left.
If you look at the history of human exploration, discovering new lands has not led to immediate settling or the establishment of long-term relationships with the locals.
If you look at the history of human exploration, discovering new lands has not led to immediate settling or the establishment of long-term relationships with the locals.
Assuming they do not have a prime directive.
If the universe is infinite and life is possible ( as we know it to be), then life will occur an infinite number of times.
If we just look at the observable universe, number of stars, number of planets, and habitats we see even in our own solar system, there are a lot of shots on goal.
If we just look at the observable universe, number of stars, number of planets, and habitats we see even in our own solar system, there are a lot of shots on goal.
I don't think that's the right way to think about infinity. Just because the chances are infinite and you know goals are possible, it does not mean that there will be infinite goals. There are infinite numbers between 4.0 and 6.0 but only one of them is a prime.
> There are infinite numbers between 4.0 and 6.0 but only one of them is a prime.
Primality only applies to natural numbers, so there can't be primes between 4.0 and 6.0. There is one between 4 and 6, but that's a finite range.
Primality only applies to natural numbers, so there can't be primes between 4.0 and 6.0. There is one between 4 and 6, but that's a finite range.
The concept holds. Perhaps the example isn't great, I'm not sure - but since when does 'the set of numbers between 4.0 and 6.0' not include the natural number 5?
That's a set of real numbers, and primality is not defined for real numbers, so 5.0 can't be a prime. The whole concept is just not applicable unless were talking about natural numbers, in which case the set is finite.
Who said it's the set of real numbers? I don't remember adding any notation that specified the set must be real numbers.
But you can't score 4.1 goals. You can't take 5.9 shots on goal. Goals and attempts are integers. Ask Sheffield United.
I feel like this misses the point. Infinite outcomes != all outcomes.
What you stated is certainly true, but Infinite outcomes == all possible outcomes in infinite quantity, and we know that life is possible.
> infinite outcomes == all possible outcomes in infinite quantity
No it doesn't. This is a common misunderstanding of infinity. Infinite is absolutely not the same as all.
No it doesn't. This is a common misunderstanding of infinity. Infinite is absolutely not the same as all.
[deleted]
First tell me what intelligent means....then we can make that bet ;)
[deleted]
Sorry, but I always thought the equation meaningless...
I agree - it's basically just a way to arrive at a meaningless number by multiplying a whole lot of wild-ass guesses together.
Do we have anything better, though?
Do we have anything better, though?
Yeah, that's probably the point. You have to start somewhere.
Personally I'm blown away that some parameters, like the fraction of those stars that have planets, we are able to capably plug values in for.
I really never thought we'd be able to get statistics for things like that in my lifetime.
I mean short of faster-than-light travel, I had assumed ignorantly that astronomy would be stuck more or less where it is for centuries to come.
Personally I'm blown away that some parameters, like the fraction of those stars that have planets, we are able to capably plug values in for.
I really never thought we'd be able to get statistics for things like that in my lifetime.
I mean short of faster-than-light travel, I had assumed ignorantly that astronomy would be stuck more or less where it is for centuries to come.
Amazing isn't it? I really appreciated 'archives of the universe', which describes the chronological advancement of astronomy since the ancient Greek. Often by simply annotating the original works or papers. Amazing to see how humanity has gained insight piece by piece, thanks to the hard work of a select group op people.
https://cmsw.mit.edu/archives-of-the-universe-marcia-bartusi...
https://cmsw.mit.edu/archives-of-the-universe-marcia-bartusi...
I wrote a presentation for undergrad on the equation; and that was the focus. I went through each value and talked about the bounds for each value and arguments for those bounds. We’re still incredibly ignorant, but the bounds on the values have improved a lot. At the time the equation was written, it was assumed other stars had planets, but it wasn’t known and the value could have been anything. Now we know the f_p ≈ 1.
I see it as a way of focusing the discussion. The numbers we could plug into it are mostly all wild guesses, but the exercise of plugging in different numbers can still be instructive.
For example, we now know there are a huge number of planets out there, and even planets in the habitable zone. Yet we haven't found any extraterrestrial life, so that suggests maybe the other factors are smaller than we initially would have guessed.
For example, we now know there are a huge number of planets out there, and even planets in the habitable zone. Yet we haven't found any extraterrestrial life, so that suggests maybe the other factors are smaller than we initially would have guessed.
It is a fabulous equation which describes the factors that would contribute to alien life. It can inform how to think and pursue SETI and gauge our current knowledge. Any result that you see bandied about is meaningless because we don't know the inputs.
Because....?
And deeply flawed...
I actually have a theory about why we don't see (any) alien society at the moment.
Step 1: recognize that all life needs to consume energy from somewhere (regardless of Carbon based or AI ones)
Step 2: realize that albeit the total energy contained in the universe is probably going to be enough for any civilization out there, regardless of type, the total amount of energy that the CURRENT TECH LEVEL allows to harvester is never going to be really large enough to treat it as infinity.
Step 3: assume that some individuals of any civilization wants to grab as much energy for itself as possible.
Step 4: Combine 2 and 3, and we reach the conclusion that the said individuals will always try to bar others from gaining enough energy, which means an expansion of the gap between the "rich" and "poor", and most importantly lead to a shrink of education of the "poor"s can benefit from, and ultimately destroy the "tech base" of any civilization. The "tech base" is the least amount of individuals that can generate some tech/science genius like Einstein/Newton who can propel the civilization forward greatly.
Step 5: I'd argue that this destruction of "tech base" almost surely occurs before the civilization reaches the point that general AI (or whatever that can substitute the original "tech base") arrives.
Step 6: Tech/Science advances slowly afterwards and ultimately the civilization won't reach very far into the depth of the universe.
Step 1: recognize that all life needs to consume energy from somewhere (regardless of Carbon based or AI ones)
Step 2: realize that albeit the total energy contained in the universe is probably going to be enough for any civilization out there, regardless of type, the total amount of energy that the CURRENT TECH LEVEL allows to harvester is never going to be really large enough to treat it as infinity.
Step 3: assume that some individuals of any civilization wants to grab as much energy for itself as possible.
Step 4: Combine 2 and 3, and we reach the conclusion that the said individuals will always try to bar others from gaining enough energy, which means an expansion of the gap between the "rich" and "poor", and most importantly lead to a shrink of education of the "poor"s can benefit from, and ultimately destroy the "tech base" of any civilization. The "tech base" is the least amount of individuals that can generate some tech/science genius like Einstein/Newton who can propel the civilization forward greatly.
Step 5: I'd argue that this destruction of "tech base" almost surely occurs before the civilization reaches the point that general AI (or whatever that can substitute the original "tech base") arrives.
Step 6: Tech/Science advances slowly afterwards and ultimately the civilization won't reach very far into the depth of the universe.
1500 years ago, or less, in Europe we see societies that were drastically poor (by modern standards), poorly educated/no formal education (the average person) and insanely unequal society (Kings and warlords vs. Serfs and slaves) where borders (resources) were being fought over and tech was very low relative to today and even relative to a few hundred years earlier (not to get into a dark ages dispute, but the Panethon would not have been able to be build in 500AD in Western Europe).
Yet this society managed to advance just fine. We are as far away from them as a Sun harvesting civilization is away from us.
Civilization finds a way.
At some point great minds become less important. Cutting edge research today is not coming from Patent Office clerks, it comes from large research teams that are constrained by budgets not human resources.
Yet this society managed to advance just fine. We are as far away from them as a Sun harvesting civilization is away from us.
Civilization finds a way.
At some point great minds become less important. Cutting edge research today is not coming from Patent Office clerks, it comes from large research teams that are constrained by budgets not human resources.
> Civilization finds a way.
There's neither any strong guarantee of this, nor any shortage of historical counterexamples.
There's neither any strong guarantee of this, nor any shortage of historical counterexamples.
We have thousands of years of human civilizations rising and falling and rising again.
Each time the civilisation collapsed it's demise was brought by much stronger technological means. We might get to a point in time in which a a full restoration is not possible.
One of such outcomes is of course an atomic war, but I'm more concerned with the receurring "underdog revolts".
Historically the elites are always getting more stagnant and the line between the capable and the mass is blurring. Most of the revolutions were started not by the workers, but by the "middle class". Basically at some point the "almost haves" convince themselves that they are more capable than the current structure and they pull the workers into the madness. Look at all the ancient military revolts, at countries that fell to fascism or communism.
So far it always begun with losers taking up the tools of their masters. Things that they were not capable enough to create in the first place. The winners create the tools of their own destruction. Communists took over the "means of production", christianity the fruits of enlightment.
At this point of time, if the mass surveilance system and the information brokers fall into the wrong hands it may be impossible to recover, even if there is no military conflict. One might argue that it already happened to large degree.
One of such outcomes is of course an atomic war, but I'm more concerned with the receurring "underdog revolts".
Historically the elites are always getting more stagnant and the line between the capable and the mass is blurring. Most of the revolutions were started not by the workers, but by the "middle class". Basically at some point the "almost haves" convince themselves that they are more capable than the current structure and they pull the workers into the madness. Look at all the ancient military revolts, at countries that fell to fascism or communism.
So far it always begun with losers taking up the tools of their masters. Things that they were not capable enough to create in the first place. The winners create the tools of their own destruction. Communists took over the "means of production", christianity the fruits of enlightment.
At this point of time, if the mass surveilance system and the information brokers fall into the wrong hands it may be impossible to recover, even if there is no military conflict. One might argue that it already happened to large degree.
*Pantheon (ou you mean the Phartenon in Greece?)
The Pantheon (the back part) does look like a giant Panettone to be fair
The Pantheon (the back part) does look like a giant Panettone to be fair
Let me tell you the good word of Roko.
A purely scientific view says there is just as much proof of aliens as any other "never found" element or being that we have "believed" existed. This includes all fairy tales and religions.
Its incredibly sad to see so many intelligent people spend very real money and time on fantasies... Not for entertainment but instead under the guise of seeking scientific truth.
Its incredibly sad to see so many intelligent people spend very real money and time on fantasies... Not for entertainment but instead under the guise of seeking scientific truth.
I think alien life is a step more likely than those other things. "Alien life" is much broader of a concept than fairy tales, and we have one piece of hard evidence for it's possibility in our own existence - it's not just made up out of thin air like say, dragons or unicorns.
I think it says something beautiful about humanity. The desire to find truth and wonder, no matter how small the chance of success.
I like to imagine that humans or protohumans left Africa not just for resources but because they wanted to know what was out there beyond the next mountain, river or ocean.
I like to imagine that humans or protohumans left Africa not just for resources but because they wanted to know what was out there beyond the next mountain, river or ocean.
I’m willing to bet if there was a similar project blowing similar amounts of money trying to find purple flying unicorns there would be a similar argument made against that endeavour.
And everyone would see how ridiculous an argument that it is to equate the two.
And everyone would see how ridiculous an argument that it is to equate the two.
Drake reasoned that if planets like Earth orbited stars like the sun, then those worlds might be populated by civilizations advanced enough to broadcast their presence to the cosmos. His logic made sense: For the last century, Earthlings have been making these sorts of announcements all the time in the form of TV and radio broadcasts, military radar, and other communications that leak into space.
His logic made sense in the context of an adolescent civilization. We broadcast stuff, so if there are other civilizations out there, surely they would do the same, right?
Doubtful, because that's too risky. Why would anybody want to attract attention to themselves?
His logic made sense in the context of an adolescent civilization. We broadcast stuff, so if there are other civilizations out there, surely they would do the same, right?
Doubtful, because that's too risky. Why would anybody want to attract attention to themselves?
Not just risky; it's expensive.
Our radio waves are much, much quieter as all the networks switch from analog broadcast to digital and from low-density-long-range to high-density-short-range.
Our radio waves are much, much quieter as all the networks switch from analog broadcast to digital and from low-density-long-range to high-density-short-range.
I think the most detectable radio signals would come from stuff like early warning radar, not communications, anyway. Not sure if those can be compressed in a meaningful way.
the light we get from our closest neighbors is lightyears away.
I have a pet idea that if star lifting or some stellar engineering is used and it were to alter emission spectra in some detectable way that we could look for clusters of stars with the same altered emission, or just clusters of stars with some non normal emissions. At least it would be possible to scan alot of the sky quickly with a method like this.
I suppose i dont know enough about stellar spectra to know if fingerprints like this could be out there
You need to back that one up.
You're basically saying: "Assume we can eventually manipulate stars, then this follows".
And while that may be true, I'm not willing to grant you your first assumption. Why do you think anyone will be able to engineer a star? What do we have today that makes you think we can manipulate something that we can't even get within a million miles of.
You're basically saying: "Assume we can eventually manipulate stars, then this follows".
And while that may be true, I'm not willing to grant you your first assumption. Why do you think anyone will be able to engineer a star? What do we have today that makes you think we can manipulate something that we can't even get within a million miles of.
As regards frequency of civilizations occurring, I've read recently an interesting take: when we look at the Earth, each of the following milestones seems exponentially more difficult (i.e., probability density is far smaller for each):
- simple unicellular organisms to eukaryotes (~2 billion years)
- eukaryotes to multicellular lifeforms (~a few hundred million years)
- humans + consciousness + language + prehensile limbs (only a couple of million / a few hundred thousand years ago?)
In addition, if panspermia (exchange of biological material via meteorites/comets etc.) is in fact effective, the conclusion was: Earth-like planets may very well be (almost) universally covered (infested?) with one or another kind of unicellular goo; but only some tiny fraction has anything more interesting, and we could be one of the handful - or even the first technical civilization in the Milky Way.
- simple unicellular organisms to eukaryotes (~2 billion years)
- eukaryotes to multicellular lifeforms (~a few hundred million years)
- humans + consciousness + language + prehensile limbs (only a couple of million / a few hundred thousand years ago?)
In addition, if panspermia (exchange of biological material via meteorites/comets etc.) is in fact effective, the conclusion was: Earth-like planets may very well be (almost) universally covered (infested?) with one or another kind of unicellular goo; but only some tiny fraction has anything more interesting, and we could be one of the handful - or even the first technical civilization in the Milky Way.
Thread about a similar topic from 1 day ago, 152 comments: https://news.ycombinator.com/item?id=23588469
He should focus on the postal servers. Half of them are aliens, and the other half are retired man in black agents.
So I'm going to rehash somewhat some comments I've left on similar threads to this. The thought on this apparent lack of alien technological civilizations has advanced a lot since 1960 (when SETI began; from the article). I still see a lot of people stick to ideas that really don't hold up to scrutiny. The two core issues are:
1. We will find alien civilizations by their radio signals; and
2. The limiting factor on alien civilizations are Earthlike planets.
(1) is the flaw in SETI. The general argument against this goes something like this:
1. Planets are efficient ways to store matter (in that gravity binds it together) but are highly inefficient in creating living area or collecting a star's energy;
2. Entering and leaving a gravity well is expensive (in energy terms);
3. Gravity can be trivially replicated with centrifugal force using materials we already have (eg stainless steel).
4. Within 1000 years we will be capable of building space habitats that solve the above 3 problems;
5. As a consequence of the above, the natural tendency for any growing civilization will be to encompass a star with orbiting habitats.
6. Artificial structures orbiting a star, even if they're just energy collectors, would be incredibly obvious to any observer from a huge distance and would be far easier to detect than radio transmissions similar to what we do today. The tl'dr of this is that the only way to get rid of heat in space is to radiate it away. The signature of this is a function of the temperature of the object and for a huge range of temperatures this is in the IR spectrum and this huge IR signature without a corresponding visible light output is what makes it "obvious".
The first radio transmission occurred 120 years ago. In 1000 years (and possibly well before them) we'll be beyond them in terms of the signature alien civilizations would detect (in that, they'd see our IR signature first). This is of course the blink of a cosmological eye so what we're really doing is hoping to see civilizations who are at the same point we are, which is incredibly unlikely.
This ties into (2). I even saw Neal degrasse Tyson make this mistake in a talk where he posits the answer to the Fermi Paradox is that civilizations run out of planets and die out.
Planets are likely important as a cradle of life and the number of suitable planets is likely a filter of some sort but irrelevant in the long term. A star with no planetary system at all can easily be a home to a Kardashev-2 civilization. Matter can be extracted from stars directly (as a side note, extracting Helium to avoid the star going supernova is likely a useful side benefit) and/or constructed with particle accelerators (and all that energy).
What I find compelling about this argument is that it's /almost/ just an engineering problem (albeit a huge one) rather than one requiring huge advances in technology and/or "new physics". Steel is sufficient to build O'Neil cylinders and solar power is a sufficient energy source for all this (ie it's not predicated on the viability of commercial fusion power generation, which I for one am not yet convinced of, and if it is viable everything gets a whole lot easier).
The other attractive part of this is how it can be done.in a piecemeal fashion, meaning you can build one orbital, the another, and another and another. Certain other megastructures are much more "all or nothing" (eg ringworlds).
The above is the classic Dyson Swarm, originally called a Dyson Sphere but Swarm tends to be the common name now as a bunch of people have assumed (incorrectly) that a Dyson Sphere is a rigid sphere. Dyson never suggested that and no known or even theorized material could support a rigid sphere that large.
People tend to hone in to one issue or another with the above. A popular one is about waste heat. "What if they recycle it?" So with perfect recycling they've violated thermodynamics so we're just talking about increasing efficiency, at which point you've just reduced your IR signature, not eliminated it.
The natural consequence of all this is that we are relatively alone and likely the only technological species at or above our technology level within our cone of effect in the Milky Way.
1. We will find alien civilizations by their radio signals; and
2. The limiting factor on alien civilizations are Earthlike planets.
(1) is the flaw in SETI. The general argument against this goes something like this:
1. Planets are efficient ways to store matter (in that gravity binds it together) but are highly inefficient in creating living area or collecting a star's energy;
2. Entering and leaving a gravity well is expensive (in energy terms);
3. Gravity can be trivially replicated with centrifugal force using materials we already have (eg stainless steel).
4. Within 1000 years we will be capable of building space habitats that solve the above 3 problems;
5. As a consequence of the above, the natural tendency for any growing civilization will be to encompass a star with orbiting habitats.
6. Artificial structures orbiting a star, even if they're just energy collectors, would be incredibly obvious to any observer from a huge distance and would be far easier to detect than radio transmissions similar to what we do today. The tl'dr of this is that the only way to get rid of heat in space is to radiate it away. The signature of this is a function of the temperature of the object and for a huge range of temperatures this is in the IR spectrum and this huge IR signature without a corresponding visible light output is what makes it "obvious".
The first radio transmission occurred 120 years ago. In 1000 years (and possibly well before them) we'll be beyond them in terms of the signature alien civilizations would detect (in that, they'd see our IR signature first). This is of course the blink of a cosmological eye so what we're really doing is hoping to see civilizations who are at the same point we are, which is incredibly unlikely.
This ties into (2). I even saw Neal degrasse Tyson make this mistake in a talk where he posits the answer to the Fermi Paradox is that civilizations run out of planets and die out.
Planets are likely important as a cradle of life and the number of suitable planets is likely a filter of some sort but irrelevant in the long term. A star with no planetary system at all can easily be a home to a Kardashev-2 civilization. Matter can be extracted from stars directly (as a side note, extracting Helium to avoid the star going supernova is likely a useful side benefit) and/or constructed with particle accelerators (and all that energy).
What I find compelling about this argument is that it's /almost/ just an engineering problem (albeit a huge one) rather than one requiring huge advances in technology and/or "new physics". Steel is sufficient to build O'Neil cylinders and solar power is a sufficient energy source for all this (ie it's not predicated on the viability of commercial fusion power generation, which I for one am not yet convinced of, and if it is viable everything gets a whole lot easier).
The other attractive part of this is how it can be done.in a piecemeal fashion, meaning you can build one orbital, the another, and another and another. Certain other megastructures are much more "all or nothing" (eg ringworlds).
The above is the classic Dyson Swarm, originally called a Dyson Sphere but Swarm tends to be the common name now as a bunch of people have assumed (incorrectly) that a Dyson Sphere is a rigid sphere. Dyson never suggested that and no known or even theorized material could support a rigid sphere that large.
People tend to hone in to one issue or another with the above. A popular one is about waste heat. "What if they recycle it?" So with perfect recycling they've violated thermodynamics so we're just talking about increasing efficiency, at which point you've just reduced your IR signature, not eliminated it.
The natural consequence of all this is that we are relatively alone and likely the only technological species at or above our technology level within our cone of effect in the Milky Way.
Oh hey snap! I’m from Adelaide, currently living in Launceston.
Tiny aside, and because I like dreaming about actually building these structures:
I work with metal everyday and hold a trade certificate in metal fabrication / engineering.
You don’t need to go to stainless steels to achieve great strength.
There are a range of carbon steels available that have up to four times the tensile strength of regular Grade 250 steel used in most structural steel applications. The 250 refers to 250 mega pascal tensile yield strength. Ultimate tensile strength increases after yield as the steel work-hardens, but that’s what makes steel such a great building material: it yields and increases in strength before failing. Anyway, I digress.
See for example Bisalloy’s range of high tensile structural steels: https://www.bisalloy.com.au/product/bisalloy-structural/
The strength of these steels comes from the addiction of higher amounts of carbon, manganese, chromium, and molybdenum, but in far smaller quantities than required to make stainless steels.
You might want stainless steels for some exposed parts for corrosion and radiation resistance, but these are unlikely to be the main structural components due to the relative rarity and cost of the main alloying elements.
Tiny aside, and because I like dreaming about actually building these structures:
I work with metal everyday and hold a trade certificate in metal fabrication / engineering.
You don’t need to go to stainless steels to achieve great strength.
There are a range of carbon steels available that have up to four times the tensile strength of regular Grade 250 steel used in most structural steel applications. The 250 refers to 250 mega pascal tensile yield strength. Ultimate tensile strength increases after yield as the steel work-hardens, but that’s what makes steel such a great building material: it yields and increases in strength before failing. Anyway, I digress.
See for example Bisalloy’s range of high tensile structural steels: https://www.bisalloy.com.au/product/bisalloy-structural/
The strength of these steels comes from the addiction of higher amounts of carbon, manganese, chromium, and molybdenum, but in far smaller quantities than required to make stainless steels.
You might want stainless steels for some exposed parts for corrosion and radiation resistance, but these are unlikely to be the main structural components due to the relative rarity and cost of the main alloying elements.
So I'm not metallurgist but my impression is that stainless steel is used as an example because it's readily available, relatively cheap to produce and sufficiently effective. A number of megastructures require much greater tensile strength than that (eg space elevator). Sometimes those materials are theoretical, sometimes not and even when not, often we've yet to produce them in sufficient quantities for such a large engineering effrot.
But stainless steel cylinders? There's no in our technology to produce those (although producing them in space or on an airless world like the Moon or Mercury might be a challenge given our reliance on oxygen refining steel).
I don't know if there are any issues with having different alloys (eg carbon steel and stainless steel) in contact with each other. I know with other metals this can be an issue. But again, I'm no expert.
But stainless steel cylinders? There's no in our technology to produce those (although producing them in space or on an airless world like the Moon or Mercury might be a challenge given our reliance on oxygen refining steel).
I don't know if there are any issues with having different alloys (eg carbon steel and stainless steel) in contact with each other. I know with other metals this can be an issue. But again, I'm no expert.
I’m saying I don’t believe there’s any real strength benefits from adding large amounts of chromium and nickel.
316 (marine / medics grade) stainless has a yield stength if about 600Mpa, whereas high tensile carbon steels exceed that, and adding enough chromium to make corrosion resistant stainless steel makes it a pain in the bottom to work with.
You don’t need to add all that expensive chromium (11%+) to obtain high strength steels.
Dissimilar metals in contact with each other are a problem because they form a battery due to moisture and solutes, thereby causing electrolysis. This would be much less of an issue in the vacuum of space.
316 (marine / medics grade) stainless has a yield stength if about 600Mpa, whereas high tensile carbon steels exceed that, and adding enough chromium to make corrosion resistant stainless steel makes it a pain in the bottom to work with.
You don’t need to add all that expensive chromium (11%+) to obtain high strength steels.
Dissimilar metals in contact with each other are a problem because they form a battery due to moisture and solutes, thereby causing electrolysis. This would be much less of an issue in the vacuum of space.
Note that our very best IR telescopes have a resolution great enough to detect an IR signature of a Dyson swarm at a distance of about 0.2 kiloparsecs, or ~600 light years.
That is a very, very small area of the universe.
If there was a Dyson swarm out there, we would only know it if it was extraordinarily close to us.
That is a very, very small area of the universe.
If there was a Dyson swarm out there, we would only know it if it was extraordinarily close to us.
So you raise a good point. I went looking for more facts about this.
As best as I can tell, current surveys for individual Dyson swarms rely on IRAS and as best as I can tell the range is about what you say.
So there are two points worth making here:
1. This is, as far as I can tell, pretty similar to the range SETI is looking at. The power required for signals beyond that range to be detectable by us starts to get to a significant portion of stellar output, at which point you either have to assume such a civilization is is capable of the kind of astro-engineering we could otherwise detect and why are they outputting something with that much power?
2. On the Kardashev scale, you have K1 civilizations who use the power output of an entire planet (10^16 Watts in the Carl Sagan scale), K2 is an entire star (10^26 Watts) and K3 is an entire galaxy (notionally, 10^36 Watts). A K3 civilization is envisioned as Dyson Swarms through an entire galaxy (although, "civilization" is a loose concept when there's light lag of 100,000 light years from one end to the other).
I found a link to a study of 100,000 of the nearest galaxies looking for that kind of IR signature on a galactic rather than solar level. No evidence has yet been found.
The gap between a K2 and.a K3 civilization is actually not that large.
As best as I can tell, current surveys for individual Dyson swarms rely on IRAS and as best as I can tell the range is about what you say.
So there are two points worth making here:
1. This is, as far as I can tell, pretty similar to the range SETI is looking at. The power required for signals beyond that range to be detectable by us starts to get to a significant portion of stellar output, at which point you either have to assume such a civilization is is capable of the kind of astro-engineering we could otherwise detect and why are they outputting something with that much power?
2. On the Kardashev scale, you have K1 civilizations who use the power output of an entire planet (10^16 Watts in the Carl Sagan scale), K2 is an entire star (10^26 Watts) and K3 is an entire galaxy (notionally, 10^36 Watts). A K3 civilization is envisioned as Dyson Swarms through an entire galaxy (although, "civilization" is a loose concept when there's light lag of 100,000 light years from one end to the other).
I found a link to a study of 100,000 of the nearest galaxies looking for that kind of IR signature on a galactic rather than solar level. No evidence has yet been found.
The gap between a K2 and.a K3 civilization is actually not that large.
'No evidence has yet been found' has an empasis on 'yet' and suggests this may change.
K3 civs in these galaxies are ruled out are they not? The result you mention is sobering and fairly suggestive we are alone.
s
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So, will he return the taxpayer money?
I thought we cannot detect intelligent design?
They're physically surrounded by a far more advanced civilisation and it's literally invisible to them because it's incomprehensible to the ant mind, and it doesn't communicate by leaving scent trails.
We could be living inside the alien equivalent and we'd have no idea either, because we wouldn't be able to see it - never mind understand it. Maybe once every few million years something random and inexplicable would happen, but that would be all the evidence we'd get.