What Is the Search for Extraterrestrial Intelligence Actually Looking For?

Four antennas of the Atacama Large Millimeter/submillimeter Array (ALMA). Credit: ESO

Four antennas of the Atacama Large Millimeter/submillimeter Array (ALMA). Credit: ESO

The Search for Extraterrestrial Intelligence (SETI) last week got a $100 million dollar shot in the arm from the wealthy, Russian Silicon Valley entrepreneur Yuri Milner.

At the London launch of this new project, dubbed Breakthrough Listen, Stephen Hawking made some inspiring observations:

To understand the universe, you must know about atoms — about the forces that bind them, the contours of space and time, the birth and death of stars, the dance of galaxies, the secrets of black holes.

But that is not enough. These ideas cannot explain everything. They can explain the light of stars, but not the lights that shine from planet Earth. To understand these lights, you must know about life, about minds.

Somewhere in the cosmos, perhaps, intelligent life may be watching these lights of ours, aware of what they mean. Or do our lights wander a lifeless cosmos – unseen beacons, announcing that here, on one rock, the universe discovered its existence.

Either way, there is no bigger question. It’s time to commit to finding the answer – to search for life beyond Earth. The Breakthrough initiatives are making that commitment. We are alive. We are intelligent. We must know.

Logic of Life

Let’s take a careful look at Hawking’s logic. He said: “We believe that life arose spontaneously on Earth. So in an infinite universe there must be other occurrences of life.”

We have good reasons to believe that life arose spontaneously on Earth, but there are many things that “arose spontaneously on Earth” that have almost certainly not occurred elsewhere. Stephen Hawking is one of them. The English language is another.

How about Hawking speaking English with an American accent and Milner speaking English with a Russian accent, in London. How many Londons are there in an infinite universe? How many Londons with Stephen and Yuri speaking English with their accents?

If we include a little bit more detail, things get quirkier. Stephen may have had wheat, milk and orange juice in his stomach. Yuri, coffee and a banana. This whole quirky assemblage “arose spontaneously on Earth.” But arising spontaneously does not mean there will be other occurrences of it in the universe.

The mission of the starship Enterprise was “to boldly go where no one has gone before.” If that mission had been to boldly visit other planets to seek out a wealthy 51-year-old Russian named Yuri Borisovich Milner with coffee and a banana in his stomach and a brilliant Englishman named Stephen Hawking with wheat, milk and orange juice in his stomach, then Kirk and Spock would never have returned.

So whether we should expect other occurrences of something elsewhere does not depend on whether that thing arose spontaneously on Earth. It depends on how generic that something is.

Is life some generic feature of wet planetary surfaces that emerges frequently? Or is life something as quirky as coffee and bananas? We don’t know. And neither does Hawking.

Life’s Quirks

Measuring the quirkiness of something is not easy. For example, species with heads are quite common. Heads seem to be a general feature – so common among our relatives that one succumbs easily to the notion that having a head is standard issue, on Earth and beyond.

But if we go back about 600 million years, there was only one species with a proto-head on Earth, and this species was the common ancestor of all species alive today that have heads.

Heads are monophyletic, meaning they evolved once. They are as quirky as a single species. They are as quirky as a naked mole rat or a sulphur-crested cockatoo. Couldn’t “life” be similarly quirky?

Our inefficient use of energy makes the Earth shine at night. If natural aliens are less wasteful, their planets will not shine. Credit: Craig Mayhew and Robert Simmon, NASA GSFC

Our inefficient use of energy makes the Earth shine at night. If natural aliens are less wasteful, their planets will not shine. Credit: Craig Mayhew and Robert Simmon, NASA GSFC

Shining Lights

Hawking also said that to understand the lights of Earth, you must know about life and minds. What are these lights that shine from planet Earth and what do they mean? I think those lights mean that someone left the lights on.

All of those lights are inadvertent waste. For the past 100 years the Earth has been wastefully beaming radio and TV signals into the universe, not because we wanted to share “I Love Lucy” with the universe, but because our broadcasting strategies were primitive.

This “shining of the Earth” that Stephen suggests is a sign that the universe has become aware, is maybe more correctly interpreted as a sign that something on Earth has become wasteful.

As we become more knowledgeable and efficient, signals that were once broadcast into space are squeezed into fibers. Earth will soon stop broadcasting its millions of mobile phone conversations. Routers and cell towers will migrate into the wallpaper of every living room. The Earth will stop shining.

The conspicuous consumption of resources and the inadvertent beaming of info-waste into space will end.

Magic of Life

Arthur C. Clarke wrote that “any sufficiently advanced technology is indistinguishable from magic,” but I think Karl Schroeder’s modified version may be more relevant for SETI searches:

Any sufficiently advanced technology is indistinguishable from Nature… Either advanced alien civilizations don’t exist, or we can’t see them because they are indistinguishable from natural systems.

Being “indistinguishable from Nature” is an interesting concept. I even wonder if we are “indistinguishable from Nature.” Maybe the universe is full of invisible tree-hugging “natural” aliens living sustainably on their planets – not polluting the universe with their info-waste.

If Schroeder is right and these indistinguishable-from-Nature aliens are the only kind that survive the tests of time, then, to find them, SETI searches will need more than Yuri Milner’s $100 million dollars. Still, I wish them luck. When new instruments are trained on the sky, we often discover something new about the universe.

The Conversation

This article was originally published on The Conversation.

CATEGORIZED UNDER: Space & Physics, Top Posts
  • Ever García

    Very good article. It’s all quirky yet amusing, that’s why we’re doing it. We need to find the answers we’ve been waiting for so long to know, and we need it now.

    • OWilson

      Ah, we need it NOW!

      Like the LHC or the Mars missions, the search will be surprisingly unsatisfactory. It will be inconclusive, or at best raise many more questions. The universe is like that.

      The earth is 3.5 billion years old and man has been around for a very short time.

      If you expect all the answers in your brief appearance here, well…
      good luck!

      Or, you could always join some religion, if you already haven’t!


      • Ever García

        You are understimating human power. We’ve made developings in science at a speed never imagined before, and we’re conquering the borders of the things we considered as impossible 20 years ago. I think we are prepared to find a lot of answers, though not all, but so many that will eventually contribute to more discoverings. It’s a proccess, and as the promotors we’re doing it well.

        • OWilson

          Sorry if I implied we were not making material progress at an astounding rate.

          We have found new ways to make the laws of the universe work for us, Space exploration, computers, DNA ad genetic engineering.

          What I meant was we can describe our surroundings in mathematical terms, but the Big Questions will remain unanswered. What, How and Why?

          We are more like spiders in a dark cave, or ants in an anthill, who can thrive on our surroundings but have no concept of an elephant, or Las Vegas!

          • Ever García

            You’re not justifying your answer…

          • OWilson

            Was there a question?

  • OWilson

    Unless we can come up with a new theory of relativity that doesn’t limit the speed of light, what is out there is beyond our reach.

    The world will remain a thing of wonder in a child’s eye.

    (And a fertile ground for religions)

  • orreman

    Maybe just like the sheep herder who discovered the Dead Sea scrolls, it will be a amateur photographer or armchair theorist that finds the concrete evidence that proves were not alone…maybe that’s already happened..”UNSETTLING” -LA Times Google Mike Orrell

    • ivian

      Already happened and happens all the time. They’re not ready to admit it, ( it would open an ugly can of worms & they’d have to admit to lying all this time) so those who have encountered it are awarded tinfoil hat status.

  • stevlich

    The universe is the worst it can possibly be, a fiery hell. Our existence is a 1 in a googoplex accident. It’s the horror of all horrors.

    • OWilson

      Or, we are blessed with a goldilocks blue marble planet, teaming with beauty, life and love!

      Man can be bad, but Mother Nature is a downright cruel, inconsiderate, unfeeling, fiendish b….. looking for any number of ways to kill you.

      Earthquakes, floods, volcanoes, heat, cold, droughts, tornadoes, hurricanes, lightning, deadly diseases.

      No matter how hard you hug a tree!

  • Mike Richardson

    For any of the present searches for ETI, we’d have to hope that such intelligences don’t develop a technology indistinguishable from nature, at least until we can be more certain about the limits of natural phenomenon in the cosmos. Our first detections of pulsars were at first half-jokingly referred to as LGM’s, or “little green men,” because the regular high-speed pulses of radio waves were unlike anything previously known in nature. Searches for large artificial constructs, such as Dyson spheres, or objects like Larry Niven’s Ringworld, have been proposed. However, there are natural phenomenon that can produce shifts of starlight into infared, or block it altogether, such as dense dust clouds or debris disks. On the other extreme, away from such ambitious mega-engineering feats, would be cultures that don’t seek to expand into space, or for some reason, develop technology along different paths than ours. A culture opposed to mechanical devices, for example, might develop a technology based entirely upon biology (such as the saurian civilization in Harry Harrison’s alternate earth West of Eden series). Such races would develop much more slowly than ours, and might never venture into space or produce the energy signatures we associate with technological civilization. It’s also worth considering that humanity has only been producing electronic signals detectable from space during the last century, and modern humans have been around for tens of thousands of years. So, even if the odds may be long on detecting SETI with our current search methods, we could still be sharing the galaxy with numerous other civilizations who just happen to be quieter neighbors than we are.

    • OWilson

      Then again, they could be conserving their energy.

      Being smarter than earthlings, they may have already cut back on fossil fuels, and would not waste their windmill or solar power on beaming it endlessly into space!

      • Mike Richardson

        Regardless of intelligence, different societies have different priorities. It’s also quite possible to be intelligent and not entirely rational. One of the most depressing answers to the Fermi Paradox of “Why aren’t they here already?” is that there may be a tendency for societies intelligent enough to develop technology, to fall into the trap of using it to destroy themselves. As an optimist, I’m hoping that’s not it, and that we can avoid that fate ourselves.

        • OWilson

          The old doomsday saw of “the tendency for societies to destroy themselves”, has no merit whatsoever.

          Mankind is flourishing more than ever, and increasing technology ensures that it will continue.

          There will, of course be some weeding out and culling of the weak and less intelligent.

          Darwinism is alive and well and lurking Lol

          • Mike Richardson

            It’s true enough we’ve avoided killing ourselves off so far, though we’ve taken a fair number of other species down so far. And we’ve yet to navigate the possible hazards of a technological singularity, which could include everything from uncontrolled AI to self-replicating nanotechnology, to biological weapons of mass destruction, and dangers we can’t even guess of yet. But as I’ve said, I’m an optimist, and I hope you’re right — well, not about the social Darwinism, that’s just kinda creepy. And what’s with upvoting yourself, Wilson? I mean, it was a decent point, but nothing to high-five yourself over. Well, if it makes you feel better about yourself — though that’s not exactly leaving it to survival of the fittest, is it? Oh well, have a pleasant evening, Wilson. :)

          • OWilson

            Look up optimist, you might learn something, although it may just be one more word that has a new meaning in the progressive “newspeak” vocabulary. Hard to keep up.

            As for the uptick (now fixed), feel free to gloat about it.

            It’s all you’ve had lately :)

            Darwinism is “creepy”? Maybe you should look that up too. :)

          • Mike Richardson

            Now, now, Wilson, I don’t gloat. Anyone can make an honest mistake, and it’s a sign of maturity to admit it and move on. Besides, you’ve always got odin to provide those reliable upvotes, right? 😉 Now if we can just work on your fixation with “progressive newspeak” and your belief that common definitions of words (such as, say, “organic”) are being misapplied — hmmm, actually, you’ve provided me quite a bit of entertainment lately! Thanks. :)

          • OWilson

            “Now if we can just work on…”

            How about working on your Democratic Socialist ghettos where, peoples lives are brutal, illiterate, ignorant and totally dependent. and being milked for votes.

            Then we can worry about typos.

            Ah, liberals!

          • Mike Richardson

            Well, I’ll give you credit. It took you four posts before you veered off into political rhetoric. Don’t know how that’s supposed to relate to E.T., but it did at least take a little longer to go off on that tangent than in most posts. That’s progress, I say!

          • OWilson

            You mentioned “societies falling into traps”, and “destroying themselves”. on other planets, and “avoiding that fate”

            Just wanted to remind you that that syndrome is alive and well in your inner cities, on THIS planet, is all. They are governed (milked for votes) by people of your particular political persuasion.

            After all charity begins at home :)

    • jonathanpulliam

      “… humanity has only been producing electronic signals detectable from space during the last century…”

      Um hmm.

      This has profound implications for verifiability.

      Let’s do a little thought exercise. Physicists like things that are verifiable; things that can be replicable in the lab, so to speak.
      Newtonian, Einstein-derived, or quantum-mechanical models all “behave” rather nicely within their appropriate “scales”, if you will. Physicists, indeed, are becoming ever less dismissive, to give an example, of Hugh Everett III’s “Many Worlds” or “Multiverse” notions, despite the fact that testing or replicating quantum waveform-derived models is by definition out of the question using the earlier, time tested models posited by Newton and Einstein.

      So my point is: there comes a point when you, the scientist, need to begin, at some scale, to operate on the “faith” of highly informed “guesses”, as you simply will not have the luxury to verify and replicate, owing to the vast distances/time intervals involved, as would have been necessitated in the past to bolster a theoretical leap you might wish to posit.

      Imagine, if you will, just what “earthling” will first communicate ( 2-way ) with extra-terrestrial life. Will it be humankind, limited as he is by the “constraint” of a 186,000 mile per second message propagation delay, or will the first Earthly life form able to converse with beings outside our “neighborhood” indeed be plant life utilizing perhaps the quantum-tunneling properties of, say, chlorophyll, to “bypass” the enormous distances involved between the “many worlds” in our “multiverse” ?

  • Derek Hall

    We have no idea what we may find, if we look.
    If we don’t look, we know exactly what we’ll find….

  • Douglas Sczygelski

    With so many people on Earth starving, it is immoral to spend money on SETI. Why can’t Hawking and his buddies understand that?

    • Thecritic89

      That’s a profound stretch of morality, right there. If it is immoral to spend money on SETI because it could be spent on food for starving people then let’s analyze that statement. So, you’re saying it is immoral to use a resource that could be used to save starving people on anything but saving those starving people. Then, it is also immoral to use any resource for any other purpose than to save starving people. Since time is also a resource that can directly help starving people, or indirectly by making money that can also go to starving people, then everything you’re doing throughout the day to do anything but help starving people is immoral if it’s not directly related to meeting the immediate needs of you or your family, i.e. shelter, food, clothing, water.

      So, you want to know why Hawking and his buddies understand that but do it anyway? Because they can think further than 2 inches in front of their own face and understand that scientific understanding and furthering our own technologies serves as noble a purpose as trying to spend every extra dollar we have on solving world hunger. Which, by the way, is a much greater problem than “Oh, if only those starving people had a couple dollars, they could walk down to the local McDonald’s and get some food.” It’s a complex geopolitical issue stemming from inefficient governing, greed, corruption, and- in many places- racial and ethnic tensions.

      In a brief statement, your comment is short-sighted, logically incorrect with reference to morality, and anti-intellectual.

      • Douglas Sczygelski

        Even if we get proof from SETI that there is intelligent life elsewhere in the universe, how will that knowledge benefit us? It won’t. Most people, at least in the US, already believe it anyway. Why spend $100 million on something that is utterly useless? You talk about “furthering our own technologies.” What technologies? What has SETI got to do with that? You should make yourself more clear.

  • jimbo701

    This is how life is defined on earth.
    Life :the condition that distinguishes animals and plants from inorganic
    matter, including the capacity for growth, reproduction, functional
    activity, and continual change preceding death.
    Our search for life is based on this definition. But what if there are forms of life that don’t fit this definition but are still conscious entities? My point is there could be forms of life that we simply can’t recognize because they are so vastly different than our own and/or our science isn’t advanced enough to recognize them. Carbon based life forms might be the rarest kind in the universe, which might explain why we haven’t found another. I think it’s best to keep our minds open to the possibility that life could literally be everywhere and it’s our inability to expand on the definition that makes it so difficult to find in the universe.

  • philconl

    I’m sorry, I could barely get through the poetic non-information and misplaced hero worship.

    I know perhaps one more thing than I did prior. 100 milllion for new instruments – what those are, when anything will change, or if even this is the aged SETI computer users project, I haven’t a clue.

    So little information, and so much pure horse hockey puck speculation.

    File this one under philosophy, again.


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