Is the SETI project based on a flawed premise?

Question

Maximum signal efficiency for information transfer actually results in a signal that's indistinguishable from noise. This is a result from information theory and data compression. Advanced alien civilizations are far more likely to communicate with signals that look like static to us, and we'd never know.

doug, random non-alien signals from outer space don't all have perfectly flat Fourier spectrum either, so where are we? How do we tell them apart?

Steve, a very good answer, but such civilizations, like ours, is not likely to have the broadcasting power to reach beyond hundreds and certainly thousands of light years. So, what's the probability that cilivizations "comparable to ours at this momen" would be found so closely?

Alexander, probably one of the best answers so far, SETI hopes that some aliens are deliberating beaming "recognizably alien" signals as a calling card. But I don't see this factor in the Drake equation. How many are likely to be interested in doing this?

iridflare, have you ever examined an image compressed picture file on a hard drive? It looks like noise!

Answer 1

Then we are screwed if they are communicating in a manner that we cannot comprehend.

On the other hand, who says that they are more advanced than us? We are simply trying to detect those early radio signals from the dawn of their electronic age. Their society would have been equivalent to our 1920's technology, then.

Answer 2

Or they might be encrypting it for privacy. The SETI project is not really trying to get a clear signal. they are looking for repeating groups or patterns that would indicate a signal.
I do not know if anybody is trying to analyze chaotic patterns. I am not even sure if that would be an effective idea.
I think maybe the effect of noise enhancement of the possible signal and your idea of doing an analysis on the random noise might be good ideas.
Keep in mind that the SETI project has some features and purposes besides eavesdropping on possible spacebunnys.

Search for Extra Terrestrial Intelligence uses voluntary spare time from the private computers on the Internet. It analysis a huge amount of data. It makes NSA Cray Supercomputers seem like wristwatch calculators.
In addition to this it is in control of huge radio arrays picking up signals from everywhere in almost all the imaginable frequencies.
SETI can have more than one meaning. Extra can mean additional and Terrestrial means Earth, Intelligence is information plus the ability to process it.

All that is just gravy though, SETI has given far more information about space as a radio telescope and it was sexier to sell spacebunnies than the actual research.
(and who knows, we might get as broadcast of space Dullahue or planet Oprah yet)

Answer 3

???
In fact, a 'maximum entropy' signal has a Fourier spectrum which nearly flat across the time domain. And there is no known, natural, mechanism which can generate such a signal. Also, we've been sending out elactromagnetic signals (with varying types of modulation) for about 100 years. That's a pretty large volume of space and, if an intelligent civilization were to 'hear' it, they'd almost certainly reply with a signal which used the same modulation technique(s).

Doug

Answer 4

This assumes that the alien civilization would be that advanced.

We are advanced enough to know the same about signal efficiency from information theory and data compression and yet, our communications are readily detectable.

Given our own propensity toward detectable elctronic communications, and an assumption that may or may not be true about the relative "advanced" nature of an alien civilization, and I'd say it's a toss up. Maybe it would be undetectable, but it's not a very strong argument.

Answer 5

SETI is based on the 1960s assumption, advanced by men of that age like Carl Sagan, that advanced people would use radio broadcasting.

Apparently the Saganists never imagined that advanced civilizations, like ourselves, might use the internet, which consumes much less energy than radio broadcasting!

Answer 6

It seems that all the alien intelligence, or even alien life-form projects are based on the flawed premise that all life is carbon-based, that communication is via sound waves, etc.

Think about it--if you were an intelligent alien life form, would you want anything to do with the greedy, violent, environmentally wasteful humans on the third planet from Sol?

Answer 7

Assuming that the communication was deliberate, wouldn't it be designed to be recognised as a signal? There'd be no point in going for efficiency at the cost of it not being received.

Answer 8

The trick is to pick out repetitive patterns from that "static." That's possible, but what I wonder about is alien civilizations that communicate with some technology that we know absolutely nothing about and therefore couldn't recognize.

Answer 9

That's one of the big reasons I stopped running the program. Who would ever know an alien signal from the static we always get?

Answer 10

i agree. also we are sending out a signal on a tight beam at an object 10,000 light years away and to get a response from that signal we would have to wait 20,000 years, and no one will be left behind to receive the message, because mankind will surely have destroyed himself by then.