Edward SnowdenTalks Alien Communications With Neil deGrasse Tyson

An anonymous reader writes: Edward Snowden, the former contractor who leaked National Security Agency secrets publicly in 2013, is now getting attention for an odd subject: aliens. In a podcast interview with astrophysicist Neil deGrasse Tyson, Snowden suggested that alien communications might be encrypted so well that humans trying to eavesdrop on extraterrestrials would have no idea they were hearing anything but noise. There's only a small window in the development of communication in which unencrypted messages are the norm, Snowden said.

Comments

it's all alien spam

[Anonymous Coward]

9 out of 10 alien messages are for tentacle enlargement pills

Compression

[penguinoid]

Sufficiently advanced compression could be indistinguishable from encryption (esp. if have a standard table to draw from).

Re:Compression

[athmanb]

But if you wanted to send that compressed/encrypted data over an unstable link such as interstellar radio, you'd need to add CRC data which lowers the entropy of the data again.

Maybe they don't even use RF

[Spy Handler]

All we know is radio, and listening with radio telescopes has yielded nothing. What if they use neutrinos or some other weird method that we don't know of?

Re:Maybe they don't even use RF

[Intrepid imaginaut]

Or just as likely, highly directional communications. They're the only type that would be of much use over interstellar distances anyway, and unless they happen to be pointed straight at our little blue marble they may as well not exist.

Re:Maybe they don't even use RF

[BoRegardless]

Like Lasers, which allow them to use less power if they are transmitting their own data amongst there own solar system or galaxy.

Re:Maybe they don't even use RF

[RubberDogBone]

Or maybe they don't use radio the way we do. We've got a whole planet here full of millions of life forms and only one of them ever discovered and harnessed radio, and then only very recently. So it appears life doesn't need radio to thrive.

Humans use it because we have a need to tell our old campfire stories at a distance, and because we like to or need to talk to each other. There is no reason to suspect another species would have these same needs. None of our nearly identical genetic cousins have these needs and they're 99% the same as us. What would aliens, nothing like us, do? Well probably not what we do.

So basically, SETI makes some big assumptions that aliens would be using radio the same way we do and there is just no logical basis for that assumption.

Snowden's theory is pointless as well because there is no way to prove or disprove it. If the aliens are encrypting we may not be able to detect it. And if we can't detect it, we can't say it's there or not. So Snowden is automatically right so long as no signal in the clear is detected. Heck he's automatically right for any signal unless it happens to be in some goofball human code format like ROT13 or some such thing AND we can run the right decoder on it to get the latest Zeta Reticuli warez or b(.)_(.)bz

Re:Maybe they don't even use RF

[Anonymous Coward]

I think Snowden means to say, that if you have an uncompressed data signal there will be many repeating symbols which would stand out if we could see it.

However compressed data and encrypted data has ideally a pure random distribution of symbols, and therefor we won't be able to differentiate it with background noise (unless it is powerful random noise).

We know this is true because our own encryption methods are already ideal enough that we can't differentiate it from random noise. Compression algorithms come close but still detectable at the moment.

Re:Maybe they don't even use RF

[penguinoid]

Thing is, high entropy electromagnetic communications would be indistinguishable from noise -- and even if it weren't, it would be hard to compete with the ridiculously powerful noise of their star. Since entropy is approximately the same thing as information, we should expect to see nothing but noise even if we got a perfect noise-free replica of their communication. It'll only get worse -- higher entropy and higher directionality -- as the technological level improves.

Only way we're finding aliens is if they're also doing a SETI program and use radio waves to do so.

Re:Maybe they don't even use RF

[TheGratefulNet]

we can't differentiate it from random noise

reminds me of fox news...

Re:Maybe they don't even use RF

[narcc]

No, no. There is a clear pattern there.

I won't go so far as to suggest it's being transmitted by intelligent life, but it's an interesting signal none-the-less.

Re:Maybe they don't even use RF

[Intrepid imaginaut]

As soon as it starts spreading it rapidly becomes indistinguishable from background noise, especially over insterstellar distances. And all of that's assuming the laser isn't occluded by whatever it's targeting, which it probably would be 99% of the time. No, I fear the chances that random stray communications of whatever sort might hit us would probably be vanishingly unlikely, especially over the short period we've been listening.

Re:Maybe they don't even use RF

[meta-monkey]

Never underestimate the bandwidth of a space Winnebago full of HDDs hurtling through a Stargate.

Re:Maybe they don't even use RF

[whit3]

I think Snowden means to say, that if you have an uncompressed data signal there will be many repeating symbols which would stand out if we could see it.

Yes, exactly!

In our own telecommunication history, VHF and UHF stations broadcasting TV signals sent sync pulses (for timing, to keep the picture from jittering) periodically. Those sync pulses were a kind of modulation that would make it easy to detect; if the signal were swamped in noise, the repetitive nature meant that a FFT of the received signal + noise could be analyzed to find the signal presence.

Earth's RF spectrum presence was mainly a 50 Hz modulated broadcast (the sync signals for European television) alternating with a 60 Hz modulated broadcast (television in the US, Japan, and the Americas). I'm pretty sure Woody Sullivan at University of Washington published on this, but cannot give a specific reference.

While some 'analog' broadcast may still exist, the modern digital television signal doesn't contain that kind of modulation, and would be easily detected only if it were EQUAL OR ABOVE the noise level. That means that Earth has dimmed in its RF signal presence, by several orders of magnitude, even though the RF energy output is undiminished.

Whoa

[John Jorsett]

Maybe the scariest aspect of that idea is that they're hiding from something.

Re:Whoa

[U2xhc2hkb3QgU3Vja3M]

Yes they are. They're hiding from the cavemen with the nuclear weapons.

Aliens encrypt all their transmissions?

[darthsilun]

Sure, because they don't want the NSA or the FBI to find out about their tunnels under the border.

Oh, he meant Space Aliens? I bet they don't want the NSA or FBI to read their emails either.

Close to random but cannot be random.

[Impy the Impiuos Imp]

We know this, and have tests to verify deviation from true random noise to detect encoding candidates, even if you can't, perhaps ever, crack it.

Actually, I hypothesize this is what SETI and so on are doing. If not, they should.

It cannot be mathematically identical to true randomness over the long run, even though the closer to statistically random data you get with your encoding, the more compressed.

Encrypted is still not natural

[mbone]

I think he is confusing encryption and steganography. Encrypted signals will still require framing, will still be likely to be bandwidth limited, and so will not appear truly natural, even if we can never break the code. As the Brits found through traffic analysis in World War II, you can learn a lot from observing alien communications, even if you never decode a single word.

Re:Encrypted is still not natural

[bsdasym]

It is.. but I think it's getting... lost in the noise.

Even a nearly worst case scenario (unframed encrypted transmissions) still need to be of high enough power to be heard over the actual environmental noise, and can be detected as non-natural. Directionality of those transmissions is the much bigger problem, as others have stated. However, if we're an average civilization, there's still plenty of unencrypted unidirectional traffic being pumped around, and will continue to be for quite some time. Terrestrial radio (FM) transmissions, navigation beacons, HAM operations, and so on.

There are also high powered directional transmissions that while perhaps not carrying useful data, are still detectable because they're cyclic, like radar for weather and ATC. We also use Goldstone and Arecibo for radar mapping of asteroids, and similar projects continue because looking for dangerous rocks heading for us is important.

We are still a very radio-noisy planet, and will likely continue to be for a very long time.

The biggest problem is really still the distance. Detecting the Arecibo message sent in 1974 with an identical antenna is only possible within about 150LY, for example, and it was highly directional; the transmit power was 1MW and ERP was something like 1TW. Put it in space and you can double or triple that depending on how cold you can get the components. Detecting the significantly lower power and less directional signals we're putting out regularly would require an enormous, cold, detector. We will need something similar to have a chance at detecting them if their transmission habits match ours.

Re:There's two options

[Deadstick]

another mutual friend where he attempted to play the "i'm superior to you" card by switching into talking Russian.

I had a college French course circa 1961 with a prof who was convinced his shit smelled rosy, because -- of all the silly-ass reasons -- he could also speak Spanish. One day we were translating text from a French novel into English -- one of the simplest possible exercises in a foreign-language course -- and he turned to a student who was a recent refugee from Cuba. He said "Senor Hernandez, would you please translate the next paragraph into (visibly puffing himself up) "any language you please?"

The guy came back at him in Japanese.

Re:Why wound they radiate information anyway?

[Deadstick]

why should puny humans even expect to detect waste heat from an advanced civilisation? Surely it would make more sense to dump it back into the nearest star?

Excuse me? Of all the possible ways to get rid of heat, transferring it into a high-temperature object is the worst. You unload heat by removing it at LOW temperature. Second Law, and all that.

I wonder if he read ...

[Ungrounded Lightning]

I wonder if he read my November 24 2014 post.

In it I pointed out that modern radios, in order to approach the Shannon limit, put out signals that are very close to random noise (and essentially indistinguishable from band-limited theral noise once distorted too much for clean reception).

And that this would make the window between no radio and radio that is indistinguishable at a distance from thermal noise very short - in our case, about 120 years from Tesla and Hertz to mostly OFDM, m-QAM, and the like.