
Encryption might be the reason why we haven't heard from aliens - flying_whale
http://www.theverge.com/2015/9/21/9363863/edward-snowden-alien-encryption
======
Mithaldu
This seems nonsensical to me. Just like internet protocols, any radio
transmission is built on a layer of protocols that envelope the actual data
being transmitted.

Encryption is applied on the data layers not to hide that something is being
transmitted, but what is being transmitted.

However scientists aren't even trying to detect signals with any sort of data
in it, but merely radio emissions that _look_ like they might come from
something with an intellect.

If we haven't found anything like that yet, and encryption is supposed to be
the reason, then that means that encryption would have to be applied at the
most basic protocol layer in such a way that even the physical properties of
the emission look like the universe's background radiation. Is there currently
human technology that does anything similar to this?

~~~
jjoe
What if it's such advanced protocol layering and encryption that those alien
signals appear to us to be "cosmic noise"? Surely an advanced civilization
would have advanced communication capabilities we haven't even considered.

~~~
kanzure
> What if it's such advanced protocol layering and encryption that those alien
> signals appear to us to be "cosmic noise"?

Another interesting way to speculate is the "under our nose" concept, which is
the concept that the existing distribution of stars and galaxies, as well as
the recorded background noise, might be the byproduct of alien intervention.
Binary star systems are a popular speculative example of "starivore"
civilizations that consume entire stars that have been moved into the alien
civilization's own star system, and perhaps some combination of multiple stars
in a single system are not "naturally" occurring in the absence of alien
influence. To an unsuspecting observer, some forms of distant astronomical-
scale engineering could be mistakenly interpreted as natural astrophysics that
the observers then incorporate into their standard models when refactoring to
account for all of the observed data... Usually the simple explanations are
correct, but when your models require really insane updates to handle the
observed data, perhaps there are other explanations? At the same time though,
what recourse would we have if 99% of the visible universe was already astro-
engineered?

~~~
cgriswald
If binary star systems were systems in which stars were moved into the system,
we should see evidence of stars being moved and consumed. I have also read
about stars being created (e.g., starting a fusion process with all the
hydrogen and helium in Jupiter, Saturn, etc.).

There is currently no evidence which suggests stars are being moved. We should
see either large gravitational tugs or engines such as Shkadov thrusters. The
latter should be plainly visible. The former should be easily detected by
extrasolar planet detection methods. Unless the tugs are spherical, the light
curves of the tugs would definitely pique interest. In any case, moving a star
seems a rather extreme and expensive measure. It is probably more effective to
consume the star onsite and use the energy locally or send only the energy
back.

There seems to be no evidence of stars being consumed, either. Dyson spheres
(or swarms) have actually been searched for locally by comparing visible and
infrared wavelengths over sections of the sky. None have been found.
Intergalactic searches have also been done by looking for galaxies which glow
too brightly in the far infrared. No luck.

It is not just a question of a mistaken belief that the artificial is natural.
The properties of light are the same here on Earth as they are billions of
light years away. Further, for all those galaxies and stars to be engineered
in the same way aross billions of light years (with some points being unable
to communicate with others since the Big Bang), is all but impossible. Life
would have to evolve at effectively the same rate and come up with the same
solutions in all those hundreds of billions of galaxies (and yet somehow be
different here in the Milky Way). Given the variety of life on Earth and the
variety of solutions it has evolved, that seems unlikely.

~~~
talmand
What if these things were done so long ago that we missed our chance to
witness them?

~~~
cgriswald
There are hundreds of billions of galaxies at various distances from Earth.
When we look out at those different distances, we are also looking out at
time. So we have something of the full spectrum of galactic evolution. Even if
these events happened "long ago" we should be witnessing them somewhere.

Locally, if these events happend long ago, surely they would have been here by
now, harvesting our star.

~~~
talmand
That's also assuming such things are being being done on a large scale. My
point is that we've only had the capability to see such things recently, while
the universe is really old.

I personally just don't like definitive statements when there's no way for us
to know the whole story.

~~~
cgriswald
I am open to the idea that there is evidence we don't have yet, but based on
the evidence we do have, the original poster's point doesn't seem likely, even
with modification. I understood your point, but as the sibling poster points
out, we have the entire history of the universe essentially on display for us.

~~~
talmand
How can you be open to the idea there is evidence we don't have yet but still
make a statement that the entire history of the universe is on display for us?

------
bhaak
This is a plausible hypothesis. I don't know if somebody else has already
proposed this as a solution to the Fermi paradox.

But it doesn't even need to be encrypted communication. Highly compressed
communication is also indistinguishable from random noise.

Of course, only under the assumption, that aliens are using the same
technology as we are.

~~~
VLM
Hollywood IT proposes that people who know nothing about computers all "know"
that every computer thing that has ever been invented is trivially
interoperable with every other computer thing that has ever been invented on a
fast hollywood movie timescale given a sufficiently advanced computer mage to
recite some incantations and be treated as socially inferior if its a plot
requirement. I think everyone here is experienced enough to laugh at that.

There is an EXTREMELY close analogy in EE / telecom land where people with no
domain specific knowledge think all radio hardware, modulation methods,
protocols, are all trivially interoperable with each other. Sure... go ahead
and try to listen to trunked public service comms using a spark gap era
coherer detector, good luck with that. Or try to listen to 60s era SSB voice
using 30s era AM receiver. Higher order PSK/QAM is indistinguishable from
white noise on a non-phase oriented receiver. This is all before we get into
weirdness like trivial line coding, think of old T-1 circuits and B8ZS
"scrambling" to get around the clock sync limitations of AMI line coding. Try
to use an aircraft NDB receiver on GPS satellites or vice versa in order to
navigate. Or connect an accurate clock built to sync to WWVB to the GPS
constellation instead, or again vice versa. Telecom, being usually run at the
limit of hardware when it was new, is even less interoperable than "computers
in general". Given poor interoperation pragmatic results on our own planet,
the odds of communicating with space aliens is basically zero, even the odds
of detecting are almost zero.

~~~
blacksmith_tb
I am far from a HAM or radio pro, but doesn't SDR actually make some of this
possible? Not using ancient sets to listen to modern signals, but using one
set of kit to rule them all, as it were?

~~~
VLM
Only kind of. If someone hasn't seen fit to write the code for a 240 hz morse
code filter, you don't get one. Or a very advanced AGC filter. Those are
"easy" because you could modify an existing set of code, assuming open source
application. GNUradio has a compile/run architecture although you can build
rather highly configurable real time systems so it's "close" to programming in
real time.

Harder is something like "digital radio monodiale" which aside from having an
unfortunate acronym is a digital shortwave voice modulation scheme... without
having the specs in front it would be very hard to decide where to start.
There are military intelligence people who do exactly this stuff with captured
enemy signals, given an enormous head start of knowing the rough technology
level of the other side and maybe some stolen documents. Still its not easy
for them. A good analogy would be imagine a radio intelligence officer in WWII
heard some 8VSB over the air broadcast TV from 2015... honestly I think you'd
end up with question marks for at least 50 years trying to figure that signal
out in 1940.

Right now, perhaps we are getting a 40 dB below the noise digital data signal
from space aliens. Without any idea how to build the specific demod, we're
going to get nowhere, and a level that low below the noise floor will not show
up on any normal waterfall so we'd likely miss it.

Existing modes tend to reflect hardware ability. So some gear some of the time
is stable enough to use WSPR modulation which is an ultra low bandwidth
digital mode for HF (shortwave)... some gear drifts in frequency too much to
use it, today. Oscillator stability can be improved to make it work, but
replacing the IF stages with A/D converters won't do it, takes more than just
doing demodulation in software with SDR instead of in hardware to fix the root
frequency stability problem. Its possible space aliens modulation method would
assume close in phase noise or IMD performance beyond 2015 capabilities,
because for them its trivial star trek dilithium crystal stuff or whatever,
but we're not going to invent the noise free monochromatic oscillator for
another 150 years or whatever, so the front end performance of our radios
wouldn't be good enough even with a preprogrammed SDR on the back end to
demodulate. Another example, we don't have the technology today or the legal
framework to do "real" beyond ultra wide band RF work, but there's no reason
to think space aliens wouldn't.

------
d_theorist
A slightly-off-topic thought related to the Fermi question.

What actually is the _point_ of communicating at sub-luminal speed between
star systems or galaxies, _other_ than CETI projects? The delay between
transmissions would make such communication impractical for day-to-day
purposes.

Perhaps this is one possible explanation for the apparent lack of such
signals. Either the aliens don't bother much with communicating at galactic
scales, or they have developed a system of doing so at super-luminal speeds
that eludes our current understanding of physics.

If this is correct then you would expect most artificial radio signals to be
easy to detect and decipher, because the only plausible use for such signals
is long-term communication with alien civilisations. And you might also not
expect to find many of them.

~~~
talmand
Seems logical to me that a civilization advanced enough for interstellar
travel would have solved the problem of the extremely slow radio wave for
interstellar communication. I would think we shouldn't be limiting such
possible civilizations with the limitations we currently face.

------
nabla9
Don't even have to be encrypted. Just compressing the data makes it hard to
separate from noise.

Turbo Codes and LDPCs used to transmit data over noisy channels (like NASA
uses in deep space satellite communications or UMTS and LTE networks) look
just like noise. I don't think Seti or astronomers have ever tried to analyze
noise for some alien codec that might be transmitting.

~~~
jerf
"I don't think Seti or astronomers have ever tried to analyze noise for some
alien codec that might be transmitting."

They can't. "It looks like noise" isn't a metaphor, it's a mathematical
truth... it is _indistinguishable_ from noise.

This is, IMHO, another one of those cases where people like to do a bit of
social signaling with their fashionable misanthropism, but we actually know
quite a bit about this problem. The optimal solution for using the
electromagnetic spectrum for signaling, even with our current level of
technology, is to use it in such a way that it looks like noise due to
compression and due to not using any more power than necessary, in any
direction other than the necessary one. _Of course_ aliens do not sit there
using four or five (if not six) orders of magnitude more power than necessary
by broadcasting in all directions instead of using a directional beam, and _of
course_ they do not sit there and transmit in an uncompressed format that is
an obvious signal, so _of course_ we don't see their transmissions. It would
be bizarre if it were otherwise. We have no reason to believe that aliens, who
live in the same universe as us and are subject to the same engineering
constraints as us, would be particularly prone to missing this incredibly
obvious optimization.

(Math may be the one true cross-universe universal, but within this universe
engineering is pretty universal too.)

~~~
TheOtherHobbes
Problem - humans have been doing all of the above for decades, occasionally as
a deliberate attempt to communicate, but mostly by accident.

So I can't see how your comment has any basis in fact.

You're only going to compress a data channel if you're in a hurry. When a
message is going to take decades or centuries to get somewhere, you're more
likely to keep the encoding as simple as possible to increase the chances of
reception.

Besides that, I can't imagine radio being used for interstellar communication
at all. It's fine for "Is anyone there?" but unless your aliens live at
geological rather than biological rates, it's far too slow for almost anything
else.

~~~
jerf
Compressing increases bandwidth, which is forever going to be at a premium. If
you want to improve reception reliability, you put error correction on top of
that. This is all off-the-shelf tech here on Earth, to say nothing of what
aliens can come up with.

"Besides that, I can't imagine radio being used for interstellar communication
at all. It's fine for "Is anyone there?" but unless your aliens live at
geological rather than biological rates, it's far too slow for almost anything
else."

Well, it's the fastest thing available unless you're basically willing to
hypothesize magic. Anyone willing to do so is welcome to do so, and I'm
serious about that; I just advocate that you be _aware_ that you've switched
to advocating magic. There's a difference between reasonable speculations
based on real physics and arbitrarily advanced engineering, vs. new physics
that despite all our research we still have little more than a whiff of, if
that, and keeps crawling into ever more exotic energy domains to even peek at.

------
radmuzom
Is there any point of this article? (serious question)

Or perhaps this was just some light-hearted conversation which has been
reported as "news" because Snowden was involved. I can as well say that we
have not yet heard from the aliens because we are yet to discover the Mass
Relays and the Citadel (apologies to those who have not played the Mass Effect
series of video games and this statement makes no sense).

~~~
jordigh
Relevant xkcd:

[https://xkcd.com/799/](https://xkcd.com/799/)

------
tired_man
Just because Snowden says something does not make it newsworthy.

It's more likely that we and the aliens wouldn't be using the same technology.

~~~
Bud
Kind of a facile statement. Radio waves are radio waves. The spectrum is the
spectrum.

Any intelligent aliens are very likely to be using the electromagnetic
spectrum for wireless communications. They might use it in somewhat different
ways, but the technology is still essentially the same.

~~~
marcosdumay
For intraplanetary communication, yes, I'd agree. But those signals shouldn't
be strong enough for us to detect (otherwise, what a wasteful species).

Now, for interplanetary signals, radio does not look that interesting.

There's the problem that it, like everything else, is jut too damn slow. So
just the assumption that long distance communication is common is already
iffy.

Then, radio is either too hard to manage, or has a too long wavelength. Yes,
some hyper intelligence out there may think differently, but from our current
understanding, it looks way more likely that such hyper intelligence will
still find it easier to send matter, neutrinos, or whatever it is that
composes most of the Universe.

~~~
norea-armozel
>For intraplanetary communication, yes, I'd agree. But those signals shouldn't
be strong enough for us to detect (otherwise, what a wasteful species).

Many of our radio signals are detectable from terrestrial sources such as
radio and air TV stations. Even Ham radio signals throw out enough power for
their signals to be easily detected beyond our solar system.

~~~
cgriswald
Eh, not really "easily." If a comparable civilization was located around Alpha
Centauri, we would have to focus the equivalent of an Arecibo radio telescope
at it for many months, maybe a year, to detect its presence. That's "easy" in
the sense that we could do it, but it's also very expensive to do and we won't
do it without having at least some idea that a civilization exists there
already. The farther out we go from Earth, the harder it is, and it gets
impossible (in the sense that we lack the resources to do it) very quickly
with increasing distance.

For interplanetary communication, tight beams would make way more sense than
broadcast. And unless one of those beams is directed at us, we aren't likely
to intercept it. This is really what SETI is looking for because it's the
easiest thing to look for.

~~~
norea-armozel
Yeah, but the fact remains that it's more likely we'll get a random stray
signal before we'll get an intended broadcast from another civilization. I
just don't see it as being one of those things any civilization is likely to
do (what's the point of communication with another civilization at such
extreme distances?).

~~~
tired_man
If they determine that the random signal contains any sort of information,
even if we can't understand it, I think they'd simply be happy to have
confirmation of another civilization.

Getting a chunk of signal with modulation or one containing repeated patterns
would be a world changer.

------
nbush
Anyone remotely interested in this idea should check out Stanislaw Lem's His
Master's Voice [1], which is an entire (short) novel about how and why an
extraterrestrial message would be encrypted. It's worth mentioning how why
turns out to be the most compelling question.

1\.
[https://en.m.wikipedia.org/wiki/His_Master%27s_Voice_(novel)](https://en.m.wikipedia.org/wiki/His_Master%27s_Voice_\(novel\))

~~~
sn41
A brilliant book which made me think that this is how science is really done.
One of the questions is whether there is a message at all. How this message is
first suspected (due to non-pseudorandom behaviour of a fraudulent table of
random numbers) itself is a fresh idea. I found the various hypotheses in this
book itself to be a very nice. IIRC, there is also an "opera singer"
hypothesis that it is not the content of the message which matters, but its
frequency.

------
SagelyGuru
Or it might be that advanced civilisations use more advanced means of
communication. In such a vast universe, clearly superluminal communication
speeds, should they be attainable, would be used. Maybe we just need to "tune
in" properly.

~~~
rimantas
Or maybe aliens are still in the stone age.

~~~
tiatia
This is possible but extremely unlikely, hence an unscientific assumption. You
always assume the likely. That is is more likely that you are in the middle.
You could argue that ONE of the steps to intelligent life is unlikely,
incredible more unlikely as we assume. But the questions remains: Why are they
not here? I am afraid we may not like the answer, whatever it is.

[https://en.wikipedia.org/wiki/Fermi_paradox](https://en.wikipedia.org/wiki/Fermi_paradox)

Related statistics: Doomsday argument German Tank Problem Capture Recapture

~~~
rimantas
The answer is obvious to me: the chances of life are very small. The universe
is very big (that's some underestimation). So it is likely, that we are not
alone in the universe, but we may be so far apart in terms of space and time
that there will be no contact ever. Just take a look how far our signals have
travelled since we began transmitting — they only covered a small part of our
own galaxy.

------
Tepix
Another reason is that unless they want to communicate with other species,
they'd use only the minimal signal strength that is required for the signal to
reach its destination, not a signal strength that is several orders of
magnitude higher.

That and our limited brain capacity, which prevents us from recognizing and/or
understanding a message from an advanced alien civilization.

------
morsch
I like the thought, but encryption is not enough to hide it from us, it'd
require steganography.

If all communication itself on Earth were encrypted, how much of a visible
signal would we still emit? You wouldn't be able to decypher the
communication, but you'd still see that _something_ is happening that's
requires a structuring intelligence behind it. Unless they pay special
attention to not only encrypting their communication but masking it as a
natural phenomenon, steganographically.

If I shout an encoded message to you in a restaurant, the other people won't
know that I told you to order the creme brulee, but they will know that I told
you _something_. I'd have to discreetly tap my plate in order to mask it.

And even aside from that, you'd need to mask all other emissions, even those
not designed to facilitate communication. On earth, you don't have to
intercept and decrypt a rocket launch command, you can tell by the infrared
(or whatever) emissions on your spy satellite.

~~~
kabouseng
Not so much steganography, but spread spectrum communications does achieve the
effect you are looking for.

[https://en.wikipedia.org/wiki/Spread_spectrum](https://en.wikipedia.org/wiki/Spread_spectrum)

------
mcguire
Years ago, I attended a talk from a professor about a networking system using
the Lego blocks metaphor. In his examples, he had a block labelled
"encryption" and another labelled "compression" and talked about how you could
arbitrarily compose the blocks in the system.

To my eternal regret, I didn't call him on the fact that those two blocks are
not arbitrarily composable.

Both encryption and compression make the resulting data look random (and you
can't compress encrypted data), and compression seems to be a much more likely
candidate.

P.S. And spread-spectrum transmissions, as someone else mentioned.

------
d_theorist
This doesn't really make sense to me. Even if it was encrypted, you would
still be able to detect a powerful, directed radio signal wouldn't you?

------
jgrahamc
Assuming that traffic analysis is useless in this case, and there's no
unencrypted metadata.

------
current_call
If it doesn't work the first time, try it again?

[https://news.ycombinator.com/item?id=10246610](https://news.ycombinator.com/item?id=10246610)

~~~
gus_massa
From the FAQ:
[https://news.ycombinator.com/newsfaq.html](https://news.ycombinator.com/newsfaq.html)

> _Are reposts ok?_

> _If a story has had significant attention in the last year or so, we kill
> reposts as duplicates. If not, a small number of reposts is ok._

> _Please don 't delete and repost the same story, though. Accounts that do
> that eventually lose submission privileges._

