How To Make Messages Easy For an Alien Race To Understand (hackaday.com)

szczys writes: The screen on that new cellphone has amazing pixel density, color vibrance, and refresh rate. The high-end headphones you just picked up do an amazing job reproducing sound. These devices interface extremely well with humans but might not be very good modes of communication for an Extra-Terrestrial Intelligence. Sure, we haven't made contact with alien life yet. Even if they did pick up our broadcasts or space probes the relatively narrow-range of audio (narrow and low frequency), visual (slow refresh rate), and data transmission methods are likely to make no sense to non-human entities. The Voyager Golden Record took a fascinating approach to making some data available to new civilizations; it's interesting to think of other ways we might communicate with beings of fundamentally different biology.

Comments

...uhh

[JMJimmy]

Don't bother. If they have the ability to pick up the signal, they'll have the ability to decipher the message.

Re:...uhh

[CaptQuark]

Every signal that we have sent out requires them to be visually oriented. Do you think the TV signals we beam into space will make any sense to beings that communicate ultrasonically? An encoded 2D image interlaced with alternate lines 30 times a second won't be of much use to intelligent vampire bats.

What about beings from an ice planet that communicate with different temperatures of liquid methane? Or beings that communicate using pheromones? Or interference patterns of UV radiation? Or any other sensory stimuli that we haven't even imagined yet.

We also try sending out mathematical sequences we assume they will recognize, like Pi. Except many mathematicians think Tau is a better constant to broadcast. (Tau is 2 x Pi. Tau fits many mathematical equations much better than Pi.) Pi and Tau are great constants for plane geometry, but what about beings that live in water or other liquid media. Circles are very rare in water. Spheres are much more common and the use of Pi may or may not be instantly recognizable. What about a constant that describes the relationship of the volume of a sphere to its radius/diameter?

There have been many studies that show that one method of communication that covers long distances is artificial gravity waves. Until we can send or receive these signals, we might be looked at like newborns clapping their hands and thinking they are communicating.

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Re:...uhh

[Rei]

Every signal that we have sent out requires them to be visually oriented. Do you think the TV signals we beam into space will make any sense to beings that communicate ultrasonically? An encoded 2D image interlaced with alternate lines 30 times a second won't be of much use to intelligent vampire bats.

Okay, first off...

1) Vampire bats do not work that way.

2) Humans take information that our senses can't perceive all the time and turn in into forms that we can. That's what false-color images and the like are.

3) A species that can pick up the signal (as the GP posited) is most definitely able to transform signals between mediums. It's pretty much a fundamental part of any receiver technology - you take a propagating signal, turn it into data, then turn the data into a form that you can perceive.

Obviously no species is going to inherently have the recipe for demodulating the signal just handed to them - they'll have to figure it out, even if their senses are precisely the same as ours. They'll have to recognize, "hey there's a signal here, and by its pattern it doesn't appear to be naturally generated and seems to be storing data in some manner". They'll then have to reverse engineer how to pull the data out of the signal. Then they'll have to figure out how the data is structured (probably the hardest part, esp. with modern compressed digital formats). All of these apply to all beings. But once you've figured all of that out, turning it into a form that you can perceive is the easy part.

Say there's a species with no vision that can only experiences the world through ultrasound echolocation, as in what you probably intended to be your example? Once you understand that the signal is, say, periodic frames representing an array of triplet values (what we know to be RGB) and know how to decode it to that, the species may play it back by, say, an "ultrasound screen" that creates the perception of a 3-dimensional surface, with the height representing pixel intensity. Maybe they might combine all three RGB values into one height, maybe they might present them as side by side heightfields, maybe they might use one value to represent height, another to represent surface roughness, another to represent sound absorptive properties of the surface, or somesuch. They'll pick whatever is most convenient for them.

I'm not going to humour your "liquid methane temperature" communication concept because that's far too low bandwidth for a sentient species to practically use. Pheromones also. And "interference patterns of UV radiation", that depends on what you mean by "interference patterns" - you're either talking about a UV equivalent of echolocation, as above, or just visible data shifted into the UV, which is just a frequency shift on the RGB image into their visual range. We as humans do frequency shifts of astronomical data all the time, that's what every image made from a UV, X-ray, IR, radio, etc telescope is.

For any species to be able to get to the phase of being able to receive and demodulate communications, it must have at least the concept and ability to perceive 2D orientation (if not 3D), because it has to be able to align receivers with the right patch of sky. That perception can be of some unthinkably bizarre form by our standards, but it has to exist. Whatever perception of 2D it has, 2d images can be presented in that form.

Your Pi/Tau example is clearly pointless. We as humans clearly know of both constants. Sure, Pi "stands out" more to us at first glance, but if we received something that appeared to be of non-natural origin, you really think nobody would notice if the data was Tau?

Circles are no more "rare in water" than on land. The cross section of a sphere is a circle. What do you think bubbles are? Rounded rocks? Round sea life? Heck, lava underwater, unlike on land, tends to produce round structures called pillow lava. And again, if this to the point of being able to isolate faint radio

LINCOS

[aaaaaaargh!]

Read LINCOS: Design of a Language for Cosmic Intercourse, Part 1 by Hans Freudenthal, North Holland Publ. 1960. Unfortunately, he never got to publish the second volume covering more advanced concepts, but the language was further developed by NASA and by various enthusiasts later. It's still the most systematic treatment for communicating with aliens.

Re:Humility

[Anonymous Coward]

This is 'sci-fi' optimism. You assume that warp drives and hyperspace will eventually trickle down into reality. Our current understanding of physics doesn't make FTL travel for matter look very promising, and we've yet to detect anything that does. Even before humans broke the sound barrier, we observed things that did so all the time. Just like we knew heavier-than-air flight was possible, because birds exist.