is it possible there's a bunch of alien communication going on, but it's all encrypted so that it just looks like noise in our measurements?
#seti #aliens #cryptography
@2ck I imagine that even if the information itself is encrypted there has got to be some structure to the protocol of the communication, so that the other end can recognize the signal, and send a correct response... even it's all pre determined and based on precise timings or something, it would still be a pattern. Maybe if they are super slow, like if takes them thousands of years to do a handshake, we might not have enough data to notice anything yet.
@namark IDK. I could imagine a shared-key scheme where all communications are encrypted with a stream cipher and your initialization vector is pulled off a well-known generator (maybe time-based). Not even saying it's not something you couldn't do some cryptanalysis on and figure out at least that there's a packet structure, but it doesn't seem hard to obfuscate enough so that you wouldn't see the signal unless you already knew there's a signal to see and what the scheme is. If the whole point was to make your comms look like noise to other potential intelligent life, it seems, at best, medium hard to achieve.
I think the question is really what ET's communication medium is. I'm not sure what our radio telescopes pick up now and whether we could distinguish a comms signal that looked random from random noise. Maybe they occlude stars to communicate over interplanetary distances but we don't see because we're not in the right orientation to see the occlusion?
@2ck Well even if you do make a single stream indistinguishable from noise, you still need to make the noise. Assuming it's all easily detectable (which I thought is the premise), wouldn't there be clear intervals of back and forth communications? Like every now and then you would hear these weird noises coming from specific places. To hide the intervals they'd have to be broadcasting actual noise all the time, which might be even more suspicious. I assume the problem is that the place is really silent and there aren't any weird jungle noises to be heard.
@namark I was thinking there's a continuous stream. I get quickly out of my depth thinking about the physics of that, unfortunately