On the Nature of Time: Implications for Advanced Intelligence and SETI

I was reading and article in The Economist about lasers that can pulse extremely rapidly. We’re talking really fast, in the femtoseconds range (one billionth of one millionth of a second).

This got me thinking about the nature of time: Is there a theoretical limit to how fast something can happen? I’m not aware of any, but physics probably gives an answer one way or the other.

Still, even if there’s a limit somehow, there’s still quite a gigantic range. From femtoseconds to how long it takes for universes to die.

What if what we consider to be “real time” – how fast we move, talk, think – happens to be a glacial pace compared to other lifeforms? I’m not sure if biological intelligent life could have a subjective impression of time on such a scale because of limits to the speed of chemical reactions and the minimum complexity required for intelligence, but if an advanced civilization had made the transition to a non-biological substrate (such as super-computers), it would be conceivable that for them seconds could subjectively be the equivalent of millennia (or more) to us.

That would make communication unlikely. It would be a bit like trying to have a conversation with a rock. Even if you knew it was intelligent, you’d probably be bored out of your mind and either you would ignore it, or wait for it to speed up. And even if that’s too anthropocentric a way to look a the situation, there’s still the problem of saying something coherent mentioned below.

There’s always the possibility that such a fast intelligence would remembers how slow it once was, in its original bio-chemical form, and plan for future contact with lesser intelligences. Keep listening on the ‘slow lane’, in other words. But even if it did that, could it really communicate with us coherently if between each syllable it had the time to evolve and change a lot (more than Homo Sapiens has had time to evolve so far)? Even if it creates the message in its ‘real-time’ and then slows it down to send it, will the entity that created the message have much in common with the subjectively much older entity that exists by the time the message has been completely sent?

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40 Responses to “On the Nature of Time: Implications for Advanced Intelligence and SETI”

  1. Frank Says:

    Kirk had a similar problem in one of those old Star Trek episodes. His solution was to sleep with the woman in the tin-foil bikini.

  2. James Andrix Says:

    For radio SETI this is pretty much a non-issue, because light is slow. Anybody having interstellar lightspeed conversations has to be prepared to deal with years or decades of lag time, at least. (To mirror your question of coherence: Will the human senders be alive when the alien response comes?)

    This would only become an issue if they show up here, (they may have come and gone and found us boring) or if we develop some instantaneous communication system.

  3. Carl Brutananadilewski Says:

    This is why I think extra-terrestrial life forms do not communicate with us. They might be visiting earth, watching our progress for scientific or entertainment purposes, but in the time I wrote this one alien individual could have gone from the equivalent of a 1,000 Einsteins to 100,000,000,000 Einsteins. An amazing concept but I do think they, with such advanced technology, could compartmentalize their awareness so that 99.999999% is operating at near light speed while the remaining miniscule amount can function more at our speed. I’d imagine they would have the foresight and ability to shape their own evolution in whatever way they desire. We won’t know the answers until they give them to us or until we as a species reach that stage ourselves at which point the question will be moot.


  4. bren Says:

    Some have theorised that the lower limit on discernable time would be Planck Time, or the time that light could travel the Planck Length.


  5. Susie Says:

    There is a great novel that deals with this issue


    quote from wiki
    “Much of the book concerns the biologic and social development of the Cheela; a subplot is the arrival of a human vessel nearby the neutron star, and the eventual contact that is made between the humans and the Cheela. A major problem in this contact is that the Cheela live a million times more quickly than humans do; a Cheela year goes by in about 30 human seconds.”

  6. damien Says:

    What if the opposite is true, and other intelligences see us as we see atoms vibrating in a gas.

  7. kh Says:

    The reason plants don’t move around is that at the time scales they move physics does not allow them to say jump. There is a minimum speed at which jumping is possible. As you increase speed there are energy considerations. Moving that fast uses a lot of energy to a life form must have that amount of energy available and it must be worth it in an evolutionary sense to use that much rather than be slower.

  8. Alex Says:

    Of course the possibility is there, but why should a civilization that has the choice decide to speed up their lives?

    If they can replace biological body parts with equivalent different-working devices, why can’t they repair them as well and live longer instead of deciding to live faster? I’m not sure whether we would decide to slow down the rest of the world only because we could if there wouldn’t be any necessity to do so (i.e. global warming, and can we really expect such a high developed civilization to have our problems?). High speed does only make sense if your perception of speed stays the same. You may be able to move faster, but why should you? Towards what? Knowledge?

    Just to complete the thought with the fast intelligence communicating with us:
    Even if it evolves during the time which is necessary to receive its message, for us, this evolution wouldn’t change much. Let’s assume that there are living stones on a lower level of complexity and intelligence than us: A stone doesn’t care if we have computers – and the fact that we do doesn’t have any effect on the way we would communicate with it.
    But again: Why should we try to talk to other forms of life that are less developed?

  9. Alex Says:

    Yes, there is a limit to how fast things can happen. It is called Planck-time: http://en.wikipedia.org/wiki/Planck_time

  10. Sanity For Sale Says:

    interesting thought. could be quite funny. I can see this now:

    2156 – Galactic News Service:

    Human beings (‘earth’ variety) have at last made it to their first planet with life apart from their own. Unfortunately the civilization they have encountered is so far advanced both technologically and evolutionary that they can’t see anything happen. To the poor humans it all looks like a big blur. One Human was reported to have said “we are disappointed that after traveling all this way we have come across a life form which is inferior to us” once again proving the idiocy of mankind and the perpetuation of the cosmic giggle.

  11. Steve Geluso Says:

    I love this. What a wonderful train of thought. Speaking of which, I imagine any super advanced beings’ thought trains run impeccably on time.

  12. Jeff Says:

    This also brings up the possibility of intelligent life communicating extraordinarily slowly.

    A small delay introduced into a human voice conversation immediately introduces confusion, and the thought of communicating over the reaches of interstellar space leaves us contemplating whether or not communication is even possible. How do you speak to someone when it takes 200 years for your message to arrive?

    A sufficiently advanced life form may have effectively achieved immortality – imagine an advanced computer, processing information over the course of millions of years, in the form of an interstellar dust cloud or what have you.

    The incredible distances involved in interstellar space aren’t nearly as daunting if you have all the time patience that you need to communicate. Maybe each star in the sky is communicating with other stars – if we were to think of it in terms of a human vocal conversation, then perhaps each star only says a word every 500 years. When you’re speaking that slowly, it doesn’t matter at all that your voice takes 20 years to reach the person you’re speaking to.

    It seems quite terracentric to me to assume that other forms of intelligence will experience time (and lifetimes) in even a remotely similar fashion to us.

    I like your post though – this whole issue of temporal compatibility is an interesting one.

  13. Roger P Says:


  14. grey Says:

    good points, but even within biological species there are huge differences in perceived time. An elephant cannot even ‘see’ things that move too fast, while insects are able to make multiple observations, calculations, and adjustments to their flight patters before we can see where they are going.

    and not only is our perception of time possibly only one part of a much larger spectrum, so might our scale. what if quarks were made up of super-clusters of smaller galaxies? if there were life on any planets in any of those galaxies, there would certainly be no way to communicate, much less detect each others’ presence.

  15. Hosein Says:

    Watch this to get a better idea of how it looks like from “their” point of view;

  16. mark Says:

    I think it is helpful to be agnostic about time:


  17. Carl Johan Says:

    hey.. very interesting.

    this must somehow be related to the relativity theory.

    It made me think of the amount of information able to be consumed in a period of time. When we get scared or somehow need to “step up and save the day”, at least I experience great focus or concentration and sense of time comletely change.

    Also, i think that when talking about intelligence, there is no intelligence without purpose. why would there. its hard for me to explain, but it would explain why we get bored hehe…

  18. kaiise Says:

    hmm interesting half question but ultimately you explore nothing.

    aren’t you patient? would a game off chess by snail mail be abhorrent to you now you have real time internet play?
    if our real time is glacial then it would only be percuived as annoying unless it also meant communication limited by their mortality — that their lifespans and memories would be too fleeting also

    the smallest unit of time is inverse to the planck constant the shortest interval with which the smallest event can happen. there is no smaller unit theoretically. although i am a few years out of date and no long re intersted in physics

  19. Alan Carter Says:

    Two SF novels you may enjoy: Robert L. Forward’s “Dragon’s Egg” describes a visit to a neutron star where the life forms are made of degenerate matter, and chemistry happens by neutron exchange instead of electron exchange. A 70 kg alien is about the size of a sesame seed, and a human equivalent lifetime takes 15 minutes. Forward makes successful communication plausible.

    Charles Sheffield’s “Between the Strokes of Night” is a little weirder and involves the discovery of stable but very slow moving physiological states of humans at low temperatures. Sheffield’s characters have more comms problems than Forward’s do.

  20. Ed Snible Says:

    A science fiction novel dealing with this concept is “Dragon’s Egg” by Robert L. Forward. http://en.wikipedia.org/wiki/Dragon's_Egg

  21. Wayne Sheppard Says:

    There was a great SF story that explored this concept.
    Dragon’s Egg By Robert L. Forward

  22. Craig Says:

    This sort of communication between species who experience time at different rates is a key part of Iain M. Banks’ “The Algebraist”, in which a member of a “quick” species (a human) communicates with members of a “slow” species (the Dwellers). The Dwellers live for millions of years, in a society billions of years old. The attitudes of each of these species toward the other are also explored, as well as conflict and cultural differences.

  23. rrrroooooocccccckkkkk Says:

    iiiiiiiiiiiiiittttttttttttttttt tttttttooooooooookkkkkkk mmmmeeeeeeeeeee ssssssooooooooo llllloooooonnnnnnggggggg tttttoooooo rrrrrreeeeeeaaaaaaddddd ttthhhhaaaaatttt bbbbbbbuuuuttttt iiiitttttt wwwwwaaaaasssss wwwwoooorrrrtttthhhhhh iiiiitttttt!!!!!!!

  24. Ed Says:

    Go read Diaspora by Greg Egan. It deals directly with post-humans who live in software and run at speeds radically faster than flesh-based humans, and the problem of communication and mistrust between the two.

    As for the smallest possible time, it was long speculated that the Planck time is the smallest. But that result is now in doubt.

  25. VicinSea Says:

    There is another inherent time related problem concerning humans contacting other intelligent beings– Humans have developed over the last 50,000 years. Relative to the 170,000,000 years that higher animals have lived on this planet, humans are late-comers to the party. It is not unthinkable to ponder the fate of the dinosaurs. The possibility that they were on track to be the “Dominate Intelligent Species” is very real. But for a stroke of galactic bad luck, it is easy to consider they they would have been building a civilization and reaching for the stars a hundred million years ago.

    A Hundred Million years later, we are still at the start of our evolutionary process. It is possible that because we are so late in developing, that other intelligent species have simply out paced us and moved so far forward in their own evolution that they would not recognize the struggling birth pains of our civilization anymore than we recognize algae as one of our forefathers.

  26. Anders Says:

    Interesting idea. Brings another question up: when is something intelligent and when would you be able to communicate with it?
    I’m one of those guys who see the earth as a living organism because it follows a pattern based on chemical and physical laws just like ourselves. I somehow see the earth as having the IQ of a plant. Studies show that some plants communicate as well through their roots. So even though they communicate you cannot have a conversation with them because our “protocols” aren’t the same.
    If an alien species wanted to communicate with us, they could probably mimic our communication to some degree as we may be able to mimic plants communication patterns, but they wouldn’t be able to have a conversation with us about what they had in mind if it is something that are completely out of our world.

  27. M.Koppenberg Says:

    Excellent insight into this matter. Eloquently expressed as well.
    Thank you.
    I imagine Time is shaped like a body of water, i.e. it has waves, and some waves will overtake other waves. It certainly is not linear or constant.
    If you follow the website link, you will see what I mean.

  28. Dustin Parsons Says:

    Interesting idea, I didn’t even consider the generations (or iterations) of evolutionary change between the time it would take us to respond, even if it was just one sentence. Imagine a whole conversation!

    I read an article recently about how it’s most likely that any sentient being we might encounter will be robotic. This makes sense when you look at the path human evolution is taking. We are already replacing our biological body parts with mechanical ones and in the near future just about everyone will be a cyborg. The transformation to a completely robotic form will happen soon after that.

  29. J.R. Mooneyham Says:

    Those mentioning the Planck time limits are correct (as far as it goes) as those seem to define the smallest discrete instants which can exist under the usual conditions present in our universe. That is, no event can take place faster than a single unit of Plancktime.

    Plancktime and Planckspace is discussed at

    In regards to the ultimate speed of thought among advanced lifeforms– the fastest would likely be among virtual intelligences living in a software realm. In theory, they could process info very near the speed of light– though keep in mind any significant distances between essential nodes would have a noticeable slowing effect on the process. So the more physically compact and tiny the spatial dimensions were of such an entity, the closer to optimum speed it could operate. But along with shrinkage comes possible waste heat problems too…just as we see with our primitive computing hardware of today. Exacting reverse calculations have been shown to help alleviate such processing liabilities– but then you lose at least 50% of your potential maximum pace as well. Doh!

    Of course, it’s also true there may be a way to ‘cheat’ in terms of processing speed. That is, it may be possible to ‘outsource’ some processing work to other universes entirely– or in effect, to use a single Plancktime unit across a trillion trillion parallel universes at the same time. Yikes! This trick would possibly be related to the ‘quantum computing’ concept researchers are working on today– and might even be part of the solution to the mystery regarding how life itself came into being, and often manages to survive even the worst calamities via accelerated evolution. That is, the evolutionary process itself is ‘outsourced’ by DNA molecules to other universes to find a way to overcome adversity, when the circumstances become too extreme.

    References regarding this can be found near the bottom of the page http://www.jrmooneyham.com/warp.html

    I maintain a speculative future history timeline at http://www.jrmooneyham.com/future_history_timeline.html which includes ideas about a possible ‘super-fast’ race as discussed here, which I named the ‘Sol’ after their originating solar system (ours). They mostly live in a virtual realm I call ‘Fance’. Details can be seen at http://www.jrmooneyham.com/solcv.html

    I also delve into the possibilities of super-powered alien civilizations in pages which begin at http://www.jrmooneyham.com/ctcta.html

    Specifically, beginning with “13. The growing lure of inner space: Here the challenge will become one of cheap, fast, and powerful fantasy versus a slow, expensive, and difficult reality” at http://www.jrmooneyham.com/ctctc.html#section7 I cover the widening chasm of capabilities and experience which could develop between physical and non-physical beings.

    Lastly, I did all this research to support the creation of a science fiction novel incorporating many of these elements, titled ‘The Chance of a Realtime’, which can be found at http://www.jmooneyham.com/chance-realtime-toc.html

    As many of the non-novel pages include a wealth of third party research citations, there’s lots there for anyone interested in this topic to explore.

    — J.R. Mooneyham

  30. mvbigflea Says:

    How can there be a limit to how fast (or slow) something can happens? Because time is measured in numerical units, and numbers are infinite, one can always add (or subtract) from any given theoretical low (or high).

  31. vidude Says:

    “Kirk had a similar problem in one of those old Star Trek episodes. His solution was to sleep with the woman in the tin-foil bikini.”

    I though sleeping with the woman in the tin-foil bikini was Kirk’s solution to every problem.

  32. ryan Says:

    Ancient life on Earth used different materials to do the work of life. Both information storing molecules and enzymes and other cell machinery were made out of what we now call RNA (as opposed to DNA and amino acids). RNA enzymes are studied today by a small number of curious scientists. Basically everything is the same. The active site on both RNA and amino acid enzymes will have the same shape, the machinery will take the same geomoectric conformations, and perform the same reactions on the same molecules. Almost all of the basic life proceses, the crebs cycle for example, existed in the ancient times and ran with RNA enzymes. The difference between RNA and amino acid enzymes is the amino acid enzyme will perform the reaction about 1000 times as fast. So, there could be something to your theory. There does exist a form of life (well, used to be here on Earth, and the universe is a big place..) that would interpret our actions as happening 1000 times too fast to comprehend. ‘
    So perhaps there are higher life forms in the same predicament.

  33. The Bomb Says:

    Mr. Richard, these same questions of time come up all the time over at Ask Miss Priss dot com. Indeed, it’s almost uncanny (all the more so in light of her gigantic antipathy for what you and she both call “treehuggers”). According to Priss, the main thing to realize about time is that it is, in her words, “an epistemological concept, not metaphysical” — by which she means: time doesn’t exist independently of a conceptual brain. One of her more recent Q & A’s on the subject is worth reproducing here, if you’ll permit:

    March 26th, 2008

    Dear Miss Priss: Could there be time travelers from the future amongst us and if so, does that mean a time machine has already been invented?

    Dear anonymous: Your question is a fascinating one. Actually, it reminds me of a similar query people used to put to me all the time: “Do we have a fungus among us?” I’ll forgo this latter one (for now), but the answer to your question is no; there could not be time travelers from the future amongst us. The reason this is so is that time doesn’t actually exist apart from man. In a literal sense, there is no such thing as “the future.” The future simply isn’t there. (As Gertrude Stein once said of Oakland, CA: “There is no there there.”) What exists is motion; what also exists are entities in motion. Time, by definition, is “the measurement of movement.” Thus time is an epistemological word, not metaphysical. It refers to quantification. The universe has been described as “eternal in the literal sense: non-temporal; out-of-time.” What this means is that time doesn’t exist independently of man. Time, therefore, like calculus, is only a system of measurement. What does it measure? It measures motion, such as planetary revolutions around the sun. There’s a venerable old saying, with which I happen to (more or less) agree: “It’s not the size of the rise that satisfies; it’s the motion of the ocean that creates the best commotion.” What this beautiful and time-tested apothegm means to me is that in the absence of human beings, there’s no size or space; there’s no order, no disorder, no math, no future, no past, no present, no alpha or omega, no treehuggers, and no God-awful English accents. There’s only the motion of the ocean. If, however, there were time travelers from the future amongst us, your surmise would indeed be correct: a time machine would have already been invented. When? “Who knows where the wind goes when it is calm?”

    Said Voltaire.

    From Ask Miss Priss dot com.

  34. Steve Says:

    There’s a fairly frequently anthologised science fiction story about first contact with an alien ship: we realise that they’re sending all their messages as high-speed bursts for some reason of efficiency, so we send our messages sped up also. Eventually they land on Earth, but we can’t see their ship: there is a series of messages from them asking if they’ve been tricked: our world is huge, murky and high-gravity, and the field they’re in is full of blob creatures. In fact, the aliens are microscopic, and live at super-high speeds naturally.

    Secondly, I think George Dvorsky posted something critical of a Singularitarian a while back – they’d made a comment that to post-singularity beings, our speech would be as tedious and content-poor as the mooing of cows.

  35. Steve Says:

    Found it! Pictures Don’t Lie, by Katherine MacLean:


    A summary.

  36. Virtual Reality Could Explain the Fermi Paradox « Michael Graham Richard Says:

    […] I mentioned before, they could also think much faster, subjectively pushing back the heat death of the universe (while at the same time making […]

  37. Roger Says:

    A few questions
    1) Have we considered how IF we get a signal how do we interperate when it was sent? How can we find a time frame reference within the data? How would we communicate the same data?

    2) Dumb idea (on my part!). If the spooky action at a distance function works and it has been verified why aren’t we looking for signaling using that medium? How could we find a buckyball that keeps an active linked atom within itself? How would a SETI make this little item easily findable?

    Just a couple of dumb questions.

  38. Order in the Universe and Pattern Recognition « Michael Graham Richard Says:

    […] with regard to order is anything like ours. This could be one more thing, along with a possible difference in subjective time and many others, that could make communication […]

  39. Roger Says:

    Communication speed mismatches will be a big challenge. Consider our actions are controlled by teh amount of energy we receive.
    If something in the cold of space communicates very slowly by our standards it would as you state create a built in problem for SETI.
    Does that built in limitation bind us to talking only with “our kind” of life?

    Once life passes into the cyborg age many of these limitations will be gone. Well past our life times though. The ability to adjust your thinking speed based on need should also enable extreme life times at that point.

    Spooky action at a distance is the best FLT method of communication possible. No light speed limitations. Imagine the challenge of finding a single linked atom (Wrong term I think it is a ion but I could be way off here) for use in communication. The secret to talking with SETI could be anywhere. How can some thing that small be made to be found? Imagine a very small craft made to convey this. It wouldn’t take much power to move some thing that small. How could it make itself noticeable? Where would a SETI put this into a solar system?
    Just few ideas. Its fun to play thought games with it though.

  40. mkhan Says:

    There are many questions about nature of time. What is time? What causes time? Why time slows in gravity? Why time slows in motion? Is time a dimension? Is time travel possible? Does past or future exist? Why is there an arrow of time? Many philosophers and scientists have tried to answer these questions with varying degree
    of success.

    Time can be defined as the presence of motion and forces. I propose that the motion and forces are due to expansion of the universe. Slower expansion of space around large masses like earth and sun could be considered as the cause of slower time linking time to the expansion of space. Gravity can be explained on basis of tendency of matter composed of billions of particles orbiting at tremendous velocities to move from faster to slower time when placed in a time differential.
    This explains why gravity is so weak yet extends to great distances and why it is always attractive.

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