Imagine this: We receive the first-ever message from extraterrestrials. We translate the communication and it turns out to be a list of planets, along with a suggestion: “Send a rocketful of deuterium to the first planet on the list. Then cross it off, write your own world’s name on the bottom and send this to all the other planets. In just a month you’ll receive a trillion shipments of hydrogen.”
Could the first alien message be a chain letter? Not likely. But ET contact remains a hot topic among some astronomers.
Communication always requires that energy be transferred from one place to another. There’s no known way around it. Whether speech (a disturbance in air) or visual signals (electromagnetic radiation), an energy delivery must take place. This means that, except for uncontrollable quantum phenomena, information cannot move faster than the speed of light. This creates a conversational time-lag that equals the alien’s distance.
In the movie Contact, the extraterrestrials lived near Vega, 25 light-years away. If we received a hello from them today and immediately replied, “Well, hi there, who are you?” it would get to them in a quarter-century. Their further response, “We’re Vegans. What’s up?” would arrive here in 2068 and our answer, “Nothing much, you?” would reach the vegetarians in 2093. Sleep-inducing.
This, of course, assumes we communicate the way we think and speak: by relying on symbolism. We say “field of sunflowers” to convey a basic concept. But the actual observation entails impossibly complex patterns of countless swaying flowers. There’s no way to disclose the scene with words.
Other lifeforms do not suffer from this limitation, and some even employ direct communicative methods. Dolphins, in an environment that can be murky, often use sound rather than vision as a primary sense. They emit intricate radarlike noises that echo like a sonogram from the target. They also have the ability to reproduce the “radar returns” that their ears perceive. So they tell their friends what they saw. But they don’t use symbolic speech. Instead they duplicate the previous sound echoes directly to “paint” the sonogramic image of the object they perceived, perhaps even emphasizing aspects of interest, into the minds of other dolphins.
Although we use symbolism and animals don’t, we’re nonetheless not isolated from the life forms around us. Each species “does its thing” and it all works out. We stick with verbal skills and yell “Stop that!” when we see Spot ripping up the garbage, but it’s our tone more than the words that lets him know how unhappy we are that the kitchen has been transformed into a scene from Dante. Meanwhile, the dog effectively “speaks” without symbology. Pet-owners learn dozens of vocalizations made by their cat, bird or dog, which convey a full spectrum of needs, comments and emotions.
Sci-fi assumes that aliens will at minimum possess the communication skills of mammals. But even lower-order animals communicate, and perhaps even bacteria do. The farther away from the mammalian realm, the more indecipherable to us is their method of information-sharing. This suggests that exchanges with extraterrestrials may be a bigger challenge than we imagine.
We start out suspecting, probably correctly, that if they’re flying through the cosmos or transmitting electromagnetically, they resemble our own technological mindset rather than taking after species like whales, who are smart but bad at things like soldering. We presume that aliens are nerdy and would enjoy technobabble. But after that, what?
Would they bother to be diplomatic? Or would they get right to the point? (“We need all your cardboard right now!”) Maybe we should first uncover their motives. Why are they reaching out? Is it intellectual curiosity, benevolence or might they be after something?
Another prospect is that communication might be impossible. If they moved through time at a different rate than we do, they could be as imperceptible to our senses as neutrinos. For any of a hundred reasons, there might not be anything to say.
But if we both desired an exchange, the standard paradigm is that math and physics would provide starting points. We always assume aliens would know about circles and pi, and realize that hydrogen is the element that dominates the universe, even though most humans don’t know these things.
It’s so unpredictable, speculation is pointless. In fact, don’t waste your time reading this. Oops, too late.
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