How to communicate with the far future, and what messages will we pass on?
There is only one structure built to last forever. Located on the west coast of Finland, Onkalo is the first permanent repository of radioactive waste ever designed: a tunnel that spirals down for 500 meters and then forks into several corridors. There, some of the nuclear waste produced in Finland is being stored. In 2120, Onkalo will be sealed with kilometers of concrete, isolating 5500 tons of highly radioactive materials to — if all goes well — never be disturbed again. The repository has to last, at least, the minimum time that its content will continue to be dangerous for living beings: one hundred thousand years.
A hundred thousand years is an unimaginable amount of time. If we went back a hundred thousand years, we would encounter human species that are now extinct, such as Homo Erectus, Neanderthals, and Homo Floresiensis. Modern humans would slowly be leaving the African continent for the first time. In the last hundred thousand years, the planet faced an ice age and a volcano that almost extinguished humanity.
Because the pace of change is accelerating and we’re experiencing an unprecedented technological explosion, the next one hundred thousand years will, most likely, be even madder. Probably language will be different, or communication will happen differently. Maybe body augmentations will mean we bypass words altogether. Possibly human beings will be physically altered; reasonably, we will be a new species. Perhaps another species will be dominant on planet Earth. But we know the nuclear waste produced in our time will remain deadly. More than 20 deep geological repositories are being built on Earth right now. This heritage has no smell, taste, or sound, but it kills.
Now we face a semantics challenge: How can we ensure that future civilizations — human or otherwise — do not enter our nuclear geological repositories and release all this radioactive material? Or, to put it simply:
How can we effectively communicate with beings that are one hundred thousand years in the future?
This problem is nothing new. In fact, there’s a whole field of research called nuclear semiotics responsible for tackling this challenge. In 1992, the United States government assembled a panel of 13 multidisciplinary experts — anthropologists, linguists, astronomers — to think of a way to signpost the Waste Isolation Pilot Plant (WIPP) nuclear deposit in New Mexico. For three weeks, professionals brainstormed several ideas for long-lasting nuclear waste markers. Carl Sagan, who was invited to participate in the panel but couldn’t attend, suggested the famous symbol of the skull and crossed bones should be placed over the repository.
But the meaning of this symbol, which for us signals danger, will likely not survive the necessary time. When it appeared just 600 years ago, the skull with crossed bones meant rebirth and eternal life before being adopted by a pirate group. Even today, cultures such as the Mexican do not associate skulls with danger.
In the next one hundred thousand years, it may be that our culture as a whole is restarted, that information is lost, and that human beings begin one or several reconstruction cycles. It might be that humans will leave Earth behind entirely, or that we inhabit purely digital metaverses. It’s likely that the reality of such a distant future is, in fact, inconceivable. Our craziest futuristic dreams may seem like utterly outdated ideas then.
Sometime within the next one hundred thousand years — during one of these cycles of evolution — it might be that someone finds whatever nuclear waste marker we decided to go for, and precisely because of it, feels invited to dig and discover the relics left behind by a primitive culture. The markers could be interpreted as having ancient religious significance, for example. For these labels to do their job, they need to convey a complex message clearly. And we need people in the future not only to understand the message but to believe in it.
For example, the tomb of the ancient Egyptian adviser, Khentika, bears the inscription, “For all men who enter my tomb… unclean… there will be a judgment… an end must be made of him… I will grab your neck like a bird… I will cast the fear of myself on him.” But this didn’t stop the archeologists from digging and entering the tomb, ignoring Khentika’s judgment. So how can we prevent something similar from happening with the warning we will place on nuclear waste repositories?
In addition to conveying a complex message, we need to choose a material that will last all this time, that resists possible ice ages, flooding, fires. It should not be beautiful, interesting, or valuable to avoid it being stolen. It should not be so small that it could be removed from the site. And we cannot rely on written language. Tamil, the oldest living language of the world, is five thousand years old and is the only ancient language that has survived all the way to the modern world. Usually, languages survive around one thousand years.
Counting on emotions as a timeless way of conveying messages, the architect Michael Brill came up with one of the world’s favorite proposals for the markers: an immense landscape of giant stone thorns that would occupy the site’s entire surface. The idea would be to make future generations feel uneasy and sad. And to avoid it becoming a kind of Stonehenge for the future, a tourist spot that would end up attracting people to the radioactive site, in the center of the space, there should be “something” to signal the following message:
“This place is a message, and part of a system of messages. Pay attention to it! Sending this message was important to us. We considered ourselves to be a powerful culture.
This place is not a place of honor. No highly esteemed deed is commemorated here; nothing valued is here. What is here was dangerous and repulsive to us. This message is a warning about danger. The danger is in a particular location, it increases towards a center, the center of danger is here, of a particular size and shape, and below us.
The danger is still present, in your time, as it was in ours. The danger is to the body, and it can kill. The form of the danger is an emanation of energy. The danger is unleashed only if you substantially disturb this place physically. This place is best shunned and left uninhabited.”
In the documentary “Into Eternity,” which reports on the difficulties of those responsible for conceiving the warning messages at the doors of Onkalo, the Finnish nuclear repository, it is argued that the best solution might be not to signal the place at all. Instead, we should just seal the entrance and hope that nobody will dig and discover this legacy our generation has left for the future. But could we hide and ignore a structure compressed of more than 300 thousand tons of heavy metals?
Deep geological deposits, like Onkalo, will be scattered throughout the Earth’s crust, so maybe a single accident would be enough for future generations to carry radiation detectors where ever they go. But what if they don’t even know what radioactivity is anymore? Maybe at some point in the coming centuries, the extraction of nuclear power will be replaced with something new. So even the very meaning of radioactivity could be forgotten over the millennia. And because it has no visible trace, it may take a long time after the release of radioactivity, and the contamination of entire ecosystems, until the cause of the problem is rediscovered.
On a brighter note, we might discover a way of stopping radiation. This would be amazing because developing a safe way of managing nuclear energy could be key to solving our current energy crisis. In this scenario, future peoples could disable all radioactive material contained in waste sites. But, unfortunately, we have no clue how to do it, especially on such a large scale, so for now, let’s go back to our nuclear semiotics puzzle.
We already know that merely erecting warning signs or structures would likely be a flawed strategy. Moreover, the media and even how to get that message across will likely become obsolete over time.
In 1989, the German semiotics magazine “Zeitschrift für Semiotik” called on philosophers and researchers to think more freely on ways to communicate the danger of nuclear energy to generations of human beings living on Earth in the far future.
For the science fiction writer Stanislaw Lem, one of the participants of the challenge, the most efficient way to communicate with the future would be through mathematics. He argues that even if a catastrophe happens, which compels humanity to restart civilization, mathematics would be discovered and used the same way we use it today because it’s a property of our universe.
But we also would have to find a way to get the message through, and only the message itself, without causing confusion with the medium.
Instead of thinking of a single material that needs to endure all this time, maybe we should expand the perspective of the challenge. How about passing on the message by keeping it alive?
Maybe we could use Lem’s mathematical proposition by storing information inside our own DNA. By storing information inside DNA, we could keep knowledge intelligible and updated through self-propagation.
The message would use living beings as vehicles to spread itself.
Building on these ideas, french author Françoise Bastide, in partnership with Italian semiotic professor Paolo Fabbri, arrived at a similar conclusion with their “Ray Cats". First, it would be necessary to genetically modify a cat species to change color when it comes close to radiation. The cats would serve as living markers. If the species is strong enough to survive a few millennia — the warning could be given. We would need to develop a cat species robust enough to pass on the radiation-triggered gene naturally instead of losing the trait over time. Finally, we would have to ensure that people decode and understand the warning. For this, Bastide and Fabbri suggest creating a piece of folklore. Folklores are powerful memes and usually are able to update themselves throughout generations to continue to be understood over time.
Most importantly, the message needs to be interesting enough for people to want to pass it on. We would have to create songs, holidays, legends, monuments about the Ray Cats, and then people could forget everything else about nuclear repositories. The only information that needs to survive is that “if the cat changes color, we must move away.”
The possibility of passing information through genes and memes seems to be the most efficient way so far, as it is the method nature itself evolved to do, and it works beautifully. We all carry, within our genome, some genes that remain unchanged for more than two billion years.
Still, it is unclear if a human-made genetic modification could survive one hundred thousand years. What we do know is that humans have used genetic modification as a technology for a long time, with artificial selection. Corn, for instance, does not evolve naturally in nature. Instead, it was developed by people in central Mexico around ten thousand years ago. Likewise, cauliflowers, broccoli, dogs, and many other beings were genetically shaped and designed by people and would most certainly not exist otherwise. So, of all human technologies mentioned so far, gene modification is the one that has survived the longest.
In the end, WIPP opted for conservative monoliths with inscriptions in seven languages, and Onkalo still doesn’t know what to do about the issue. So this is essentially a problem without a solution so far.
Furthermore, nuclear waste is only one example of how some of the current human lifestyle will have profound intergenerational consequences — some components of our electronic devices, for instance, are way more numerous and can take up to two million years to decompose.
Arthur C. Clarke once said that the Earth would become a biological museum of our history. If this is the case, it would be a dismal museum, which instead of welcoming its visitors, asks them to walk away, a museum filled with “relics” that kill. But museums are static, and our planet is alive. Every living species today has a lineage that can be traced back to billions of years in the past. Our whole planet is a message from everything that came before. Things can never be interrupted; biological evolution is unstoppable; rather, everything is in constant continuation. In one hundred thousand years from now, this whole planet will undoubtedly and inexorably carry the living message of us and of our times.