[Pigo]

That feels like too much assumption to me. The scenario described well by Michio Kaku is the only one that seems probable to me.

"Lets say we have an ant hill in the middle of the forest. And right next to the ant hill, they're building a ten-lane super-highway. And the question is 'Would the ants be able to understand what a ten-lane super-highway is? Would the ants be able to understand the technology and the intentions of the beings building the highway next to them?"

So it's not that we can't pick up the signals from other worlds using our technology, it's that we can't even comprehend what the beings from Planet X are or what they're trying to do. It's so beyond us that even if they really wanted to enlighten us, it would be like trying to teach ants about the internet."

[murbard2]

The only thing this argument has going for it is sounding wise by virtue of being self-deprecating.

If there are structured radio signals being emitted, it matters not whether or not we understand what the aliens are up to, if it hits a sweetspot between noise and simplicity we can tell it's a signal. And no, "radio waves" aren't the equivalent of "smoke signals", if there are better ways to communicate across space, that would change a lot our understanding of physics. This isn't to say that our understanding is complete, but the default assumption should be that it's very unlikely that there is a better way to communicate long distance.

Compression is an issue in that respect, but that's a different argument.

[Panoramix]

Those are huge assumptions IMO. Maybe they don't feel the need or comprehend the concept of communicating over long distances. Maybe they discovered a different force we don't know of. Just because radio waves worked for us, it doesn't mean every advanced civilization will makes use of them. The possibilities are so vast and endless.

[murbard2]

If they are a space faring civilization, they need long distance communication. No the possibilities aren't endless, there's a lot of physics that we know that strongly constrains the search space. AFAIC, I think compression is the big issue, we should be looking for forward error correcting codes in the data.

[Panoramix]

I do agree with you, but I have the feeling you have a narrow view of how these guys look like. Your argument was not too compelling. For all I know they could be giant gas clouds, silicon life forms, dark matter creatures, a fungi-like thing that spans the whole interior of a small planet and manages to shoot spores into space. Their motivations are not going to be in line with those of the average American. Their lives could span milliseconds, or aeons. Their brain could function at so extremely different rates than ours, that we or they wouldn't consider each other sentient. They could be highly intelligent* and/or propagate successfully without radio communication.

But I think we might be discussing semantics. When you say "intelligent", you probably have something specific in mind. Which probably boils down to "can do math". But a different intelligence could also grasp the laws of physics at an intuitive level, in the same way a dog can catch a frisbee. Perhaps they can "get" turbulence or higher dimensions,understand a trees as a whole, something we completely fail at.

So to me it's a stretch to think that we can find them by looking at error correcting codes. But then again, I have no better proposal.

[wlesieutre]

Laser communication seems more likely for long distance communication. Omnidirectional radio broadcasts need a comparatively huge amount of energy.

https://en.wikipedia.org/wiki/OPALS

[murbard2]

I agree, but that's a very different argument from "who are we, measly little ants to think we can understand..."

[outworlder]

> If there are structured radio signals being emitted,

Why should there be? Earth itself is getting quieter. Our electronics are more sensitive, for the applications that still use radion. For a lot of things, we are using plain boring fiber-optic (and copper) connections.

[fivedogit]

The earth is getting louder. 150 years ago, we'd have had almost zero light pollution. Nowadays you can't even see stars when you go outside.

Not only are there more lights, we are getting more efficient at producing energy to power them.

[chc]

That's noisier, but it isn't a louder signal. We're talking about detecting alien species across vast distances. You can't do that by looking at a planet's light pollution AFAIK, because giving off this level of light is just not very notable — the sun reflecting off our planet is much brighter.

[fivedogit]

But sunlight reflecting off a random planet (including ours) is not useful. Sure, you can detect it, but it doesn't say anything about whether the planet has intelligent life or not. It would just be noise in the cosmos, no signal.

I'm not a physicist, but my understanding is that all EM frequencies -- visible light, radio, infrared, etc -- travel away from earth at the same speed (c). Since space has (almost) nothing to slow them down, then they'll just keep going forever. Thus, "strength" (however you want to measure it) is largely irrelevant so long as the signal it produces is detectable apart from all the other outgoing information. So the "light" broadcast from a TV tower is the same as the light from a spotlight at a shopping mall, in terms of its ability to travel through space and get noticed by aliens.

The only exception I can think of would be our atmospheric interference. Some light may penetrate our own cloud layers better than others. So all light may not be created equal, in that sense.

[chc]

The GP was talking about how we're quieter now (i.e. using lower-powered radio signals), and you replied that we're louder because we have a lot of light pollution nowadays. My point was that AFAIK light pollution does not produce a signal for detecting life. We're producing louder noise and a quieter signal.

[throwaway41597]

Isn't encryption the bigger issue? Agreed otherwise.

[4714]

Quantium communication would be a far better alternative then to sending radio-waves through space.

[mortenjorck]

Then there's always the possibility that we're the superhighway builders and we can't see the ants. Could there be billions of worlds with life that have yet to (or more likely failed to) even evolve chordates?

What if the super-advanced aliens are us?

[mlitchard]

Yeah there's a horrorshow idea to contemplate. Humanity is the Elder Race. Yikes!

[VLM]

Agreed and please don't forget that our ants may very well have implemented a working planetary scale communications network with an overlaid sentient intelligence (can't really call it an AI) operating on that distributed computational network based on inter-nest chemical pheromone exchange operating continuously for several million years of uptime ... but ... "Hey man they're just ants, sure we don't understand them much better than dolphins or monkeys but I'm sure they're not implementing anything as important as one of our roads"

Its quite likely the beings from planet X understand omnidirectional broadcast electromagnetic waves as an interstellar communications network technology about as well as your average software developer understands arcnet or 10base5 ethernet or flint-knapping.

[netcan]

The problem with all ET intelligence analogies is that we don't have much to work with. Ants can't understand highways. Can dogs or chimpanzees? What does it even mean for a chimpanzee to understand a highway? You might get one to understand that it is for cars and you can get from place to place on it. Maybe she'll understand that we make them for this purpose. Would she understand why this is a big deal? How about a swing? Does a chimpanzee understand a swing? I have never personally known one, but I imagine that if a close friend of a chimpanzee was wont to occasionally come by with a rope and tire and construct a swing, she would eventually understand these can be sued to make swing. Is the difference between swing because the highway is more advanced or because it is more remotely related to fun?

We've got questions to answer before we make these analogies. What does intelligence mean, in the context of ability to understand such things? Is it a hurdle that we are over or a continuous scale from slug to alien? From our (admittedly biased) perspective, it seems to be.

Following from that, all these analogies about advanced civilizations destroying themselves, their planets, living in cerebra-utopian VR. These are all analogies to us, the only "intelligent" creatures we know. They're also based on a very brief period of civilization where we have been able to even conceive of our impact on the planet. Until people went to the moon, how strongly lodged in people's minds was the idea that we are on a planet?

We are not even good about extrapolating 100 years into our own future. People thought factories and technologies would lead to 2 hour workdays and a pleasure society now. How good could we be at making analogies to creatures we don't know exist.

[cgriswald]

We may not be able to understand the ten-lane superhighway, but we can certainly distinguish it from natural phenonemon.

Radio SETI is the most popular, but searches have been done in a wide variety of ways. For instance, A search for a complete Dyson swarm can be done by looking for "stars" which only emit radiation in the far infrared. Partial Dyson swarms can be detected by comparing the mag of a star at two different wavelengths. Megastructures are potentially detectable via the tranit method. And searches have been done to look for signs of galactic engineering.

I'm still willing to entertain the idea that Kaku is correct, but it mostly just seems like wishful thinking to me.

The evidence thus far suggests that even if life is everywhere in the universe, technological life may not be.

[sixQuarks]

Elon Musk disagrees with that statement. He believes once intelligence gets beyond a certain threshold (which humans have), there are no such things that are beyond understanding. Most people don't know how to write complex math equations, but that doesn't mean they can't understand what mathematics is.

[unclebucknasty]

In discussions about artificial super-intelligence (the final stage of AI that sends us rocketing beyond the singularity), our inability to comprehend what such an intelligence might desire or do is frequently accepted as a significant risk by those who fear such AI.

When one considers an infinitely and exponentially increasing intelligence that can quickly bypass the point of easily answering the questions that currently most perplex us in all fields, then it is reasonable to believe that intelligence would arrive at a level of considering (and solving) problems that we cannot even imagine, let alone understand.

Given that Elon Musk has spoken about has concern over AI, it would be interesting to hear how he integrates that with his belief that our intelligence is sufficient to understand anything.

[eridius]

We may not be able to predict what such an AI would desire or do, but I assume you'll agree that we'll still be able to observe what it does do and understand that it's doing it (even though we may not necessarily understand how it does something).

[unclebucknasty]

>I assume you'll agree that we'll still be able to observe what it does do and understand that it's doing it

No. To make that leap, I must assume the conclusion. I cannot know that I'll be able to observe what it does, because I don't know what it will do (or whether I can even perceive the dimension in which it does it for that matter).

Secondly, the word "understand" is subjective. I assume that Musk meant the word in the sense that there is sufficient depth of understanding as to actually be meaningful, else his statement itself would be meaningless (i.e. so obvious as not to be required).

[eridius]

I had a really long reply written, but before posting I went to try and find the source of the Elon Musk paraphrased belief, and I can't find it. I don't know where sixQuarks got it from, but without knowing what the source is, it's hard to second-guess what Elon Musk was actually trying to say (or whether he even said it at all).

That said, ignoring the Elon Musk bit, even if a superintelligent A.I. figures out how to communicate in some other dimension, surely there's plenty of work it will do that fits within the bounds of the physics we know, and we can observe what it does that we do understand, and we can observe what it does that we don't understand. And given time we can figure out how to understand that which we can observe. And more generally, even if it manages to jump straight to communicating in some other dimension without letting us see its intermediate work, it seems very likely that whatever it is doing will have observable effects within the realm of the physics we understand and can observe (even if it's just EM radiation). At the very least, we can tell that it's there and that it's doing something and start figuring out what it is doing.

This is in contrast to the ants of Michio Kaku, who don't even know anything is going on. The point isn't that the ants don't understand how to build their own 10-lane superhighway, it's that they don't even know that this is a thing built by another species or for what purpose it was built. sixQuarks's point (regardless of whether what he said about Elon Musk is true), summed up in his analogy about complex mathematics, is that we should still be able to observe aliens and comprehend that they're doing something, even if we don't necessarily understand how to do that thing ourselves.

[sixQuarks]

Here is the source: http://waitbutwhy.com/2015/05/elon-musk-the-worlds-raddest-m...

And here is the actual paragraph:

"One topic I disagreed with him on is the nature of consciousness. I think of consciousness as a smooth spectrum. To me, what we experience as consciousness is just what it feels like to be human-level intelligent. We’re smarter, and “more conscious” than an ape, who is more conscious than a chicken, etc. And an alien much smarter than us would be to us as we are to an ape (or an ant) in every way. We talked about this, and Musk seemed convinced that human-level consciousness is a black-and-white thing—that it’s like a switch that flips on at some point in the evolutionary process and that no other animals share. He doesn’t buy the “ants : humans :: humans : [a much smarter extra-terrestrial]” thing, believing that humans are weak computers and that something smarter than humans would just be a stronger computer, not something so beyond us we couldn’t even fathom its existence."

[unclebucknasty]

We may be talking past each other here and I'm not quite sure how to formulate my thoughts more clearly, but I'll try.

>surely there's plenty of work it will do that fits within the bounds of the physics we know

Simply to say some work would itself be a huge assumption, but plenty? That assumes far too much about our current state of knowledge, and it places artificial limitations on the capacity of a super-intelligence.

The flaw in your thinking is your very reliance on our own knowledge as your frame of reference. You're extrapolating from that because you can't imagine anything else. But, that's the point: we don't know what we don't know (or what a super-intelligence might know).

EDIT: I could attempt to use hypothetical scenarios here to convey how your assumptions might be wrong (e.g. what if this intelligence could jump dimensions such that our laws of physics no longer hold?). However, to do that would be to commit the same error that you're committing: it extrapolates back from our own limited language and understanding. By definition, if we can explain it, then it doesn't meet the test of the type of intelligence that I'm referencing./EDIT

Your statement is also a pretty big tell that you're working from an assumption of only marginally increased intelligence, which is where I think our disconnect really enters. To appreciate the degree of intelligence I'm referencing, see [1].

It's long, but a good read in its own right. Specifically regarding this discussion, towards the middle of the page there are two graphs, labeled "Our Distorted View of Intelligence" and "Reality" which might help illustrate the scale of what I'm trying to communicate. Here also is an attendant quote:

>In our world, smart means a 130 IQ and stupid means an 85 IQ—we don’t have a word for an IQ of 12,952

See what I mean? When intelligence reaches such a scale beyond our own, it destroys key assumptions. The idea that we can comprehend that the intelligence is doing something is not guaranteed. Further, even if perceived, that perception itself is potentially only incrementally more representative of true understanding than not perceiving it at all. So, for any meaningful purpose, our understanding would be much more closely aligned to that of the ants WRT the 10-lane superhighway.

Another way to look at this is to imagine an infinitely expanding intelligence scale. At some zoom-level, we are pushed so much closer to the ants that the difference is virtually indiscernible.

[1] http://waitbutwhy.com/2015/01/artificial-intelligence-revolu...

[sumitviii]

I was going to make logingone's argument but here's a better one:

All maths done till ~1600 AD could have been done in 50 years, if you see it from perspective of a civilization which has a stable existence. And forgetting all abstractions, stability of surrounding civilizations is basically a random phenomenon.

And I'm sure maths done in physics departments is beyond understanding of 80% people outside it, let alone any civilization which started 400 years before us.

[tripzilch]

Okay, but there's still a difference between:

1. Knowledge that is potentially within our understanding, as humans, even if it takes a few centuries.

2. Knowledge that would require a few millions of years, because we'd need to evolve beyond our current level of intelligence, similar to what chimps, as a species, would need to do if they were to really understand theoretical physics (that is, assuming chimps would in fact evolve to higher intelligence, if there were, say no humans around).

A reasonable interpretation of Elon Musk's claim would be mainly arguing against the existence of a barrier like the type 2 knowledge. But I could be entirely wrong, I haven't read his reasoning behind this claim.

[sumitviii]

How do you think Newton would have reacted if someone said "Pentaquark" in front of him? Think he would have understood when just the word was said? Musk is talking about Newton getting all of modern physics when all he has heard is two undergrads chat on Hacker News.

[logingone]

Elon Musk is an engineer, not a philosopher, and I stand to be persuaded, but I find using him to counter Michio Kaku ridiculous.

[adventured]

A philosopher would be the first to understand that no one is or can be excluded from the realm of ideas or thought.

Being a philosopher is not an extraordinary designation, such that it puts them beyond the mental abilities of someone of Elon's obvious mental aptitude.

[logingone]

Exclusion? Oh dear, here we go with the black or white. "realm of ideas or thought" - and the simplification. "not an extraordinary designation" - and dismissing philosophy. "beyond the mental abilities" - and more simplification. "mental aptitude" - you'll be fine then with neuroscientists or some such fixing the falcon.

[pekk]

It really doesn't matter who said it, it's just good to cite the source. But there is nothing which makes Michio Kaku infallible. Arguments can't be reliably evaluated according to who made them.

[sixQuarks]

Like him or not, Elon Musk has an uncanny ability to figure things out. Of course he's wrong on some things, but for the most part, I wouldn't discount anything he says.

[ekianjo]

> doesn't mean they can't understand what mathematics is

Yet humans clearly fail to understand things like radioactivity (and the risks involved, for good or bad). I'm not sure what Musk thinks is reliable at all in this matter.

[tosseraccount]

Humans do understand radiation dangers. Why do we have no nuclear war since the atom bomb? Why are there so few deaths from nuclear power plants? Why do people use sunscreen and shield spacecraft?

[JulianMorrison]

What's odd and strange is how many ten-lane superhighways we don't see. Because while the highway may just be a "infinite stone plain of death" to an ant, it's there. But you look up in the sky and you don't see stars reduced to heat-radiating Dyson shells, or towed around by Shkadov thrusters. And you really ought to, because any civilization before us should by any reasonable dice roll, be millions of years ahead of us.

[eloff]

Understanding all the motivations for building a highway or how it is built may be beyond us currently, but we can still differentiate it from naturally occurring phenomena. All we're talking about here with the Fermi paradox is detecting evidence of intelligent life, not understanding their technology or motivations.

[joe_the_user]

This kind of argument seems like it's only appealing through it's similarity to one of Aesop's Fables.

I think as far as we know, ant's don't even ask themselves the question "what is this ant hill". Human cosmologists, on the other hand, seek an explanation for everything that they see in the cosmos. The only way some alien phenomena would be ignored would be if it seemed to have the qualities of some apparently easily explained phenomena. This is certainly possible but it seems unlikely it would happen by accident - cosmology's models for ordinary, unexceptional stars, nebula and galaxies are all fairly detailed.

[Cyph0n]

This same argument is quite validly used by people like myself (a Muslim) who believe in a creator.

[agentgt]

Yes I generally agree that this is one of the strongest explanations. Especially if you consider the small spectrum of communication we are examining (and thats just electromagnetic for all we know dark energy may provide a superior mode of communication). I just like the entertainment one because its amusing and sort of describe a great portion of our own civilization. The reality I think/hope is there will always be explorers/dreamers/big thinkers.... I hope.

[rimantas]

For me the best explanation is the size of the Universe. No other assumptions needed.

[agentgt]

Its not the size but rather intelligent entity density. You could have an infinite universe but still have high ratio of contact if the universe has a high density of life forms (think of it as collisions with particles in a large volume).

[XorNot]

Compared to the reducing human reproductive rate this is an important point. It's quite likely that somewhere in the regime of 12 billion is all the alive humans there ever will be - even with immortality technology. After all, how many times per 1000 years would you want to have some more children? How many of those people are likely to exist compared to a dormant mass who don't have children?

Now factor in a lack of FTL travel. If it takes thousands of years to go exploring, how many explorers are there likely to be, and how likely are they to stop and setup colonies instead?

[agentgt]

Yes this is similar to the self replicating probe problem (one solution to the SETI problem is to launch probes that replicate). That probes start having the same problems as the creating intelligent entity has. Either the probes can't replicate fast enough or decide to stop replicating/exploring for whatever reasons and there are just not enough/fast enough probes.

[ekianjo]

> For me the best explanation is the size of the Universe

Size, and time of the Universe. Most probably species do not last beyond a couple of million years no matter what, and there may be very little overlap between periods of intelligence even if they were in relatively close area of space.

[jboy55]

My thoughts are, its not just that ants trying to understand the superhighway. Its the beings that create a superhighway wishing to communicate in a way the ants would understand.

Maybe they'll just wait for the ants to start to build roads. Maybe what we think are roads (Electromagnetic waves) are to the beings as scent trails are to ants.