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Perhaps we are not looking in the right way

Let’s just assume that we aren’t alone, and that the universe is filled with intelligent life. So far, SETI didn’t track the correct solar system/star to spot them. However, having spend so many ours listening to the sky it seems hard to imagine they just missed them all.

Perhaps other intelligent life forms are simply not sending high power radio waves across the universe for other (perhaps hostile) life forms to detect. But perhaps they are kind enough to send some low energy signal in such a way that other life forms can detect them because all intelligent life forms (at a certain level) are sending the same low energy signal. If there are enough life forms out there this means that we would be able to detect it. Of course no information of location is revealed. Only that there is a pulse of life running through the universe.

How can we detect it?
Not with normal focused radio antennas. We need something big to "see" as much sky as possible.

But what about the Doppler shift? The further away, the more red shift in signal when it is received at our end. So a received frequency curve at earth could already tell something about the distribution of life over the universe. This however implicates that the sent frequency must be known by all senders.

But perhaps there are different ways that such alife signal could be composed such that it can be detected by us.

Let's discuss!!

Topics: alien

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    Dec 23 2012: 'Of course no information of location is revealed.'

    Well, the source of any signal is not diffuse in a three-dimensional space, and its 'volume' no protection against possible 'hostile' species...

    The difficulty in tracing any 'message' may it be intended or unintended is the sheer width and quantity of the possible 'carrier ways' and not to know what and where exactly to look for ...

    The Doppler shift would not affect the contend of any message, just its 'playback' speed. But what if a message would not use 'conventional' electromagnetic waves and would, let's say, be encoded in manipulated 'Neutrino' streams instead?
    • Dec 23 2012: Hi Lejan, could you explain to me: "Well, the source of any signal is not diffuse in a three-dimensional space, and its 'volume' no protection against possible 'hostile' species..."

      Do you mean that any signal could be traced in three-d space?

      But can you think of a way that other life forms could compose a signal in such way that its location is not revealed and you just need more sources to detect it. Is that possible when they would use encoded Neutrino's?
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        Dec 28 2012: Hello Frank,

        the origin of messages based on electromagnetic signals is traceable in 3D space, just like you find a light-house in the middle of the night by following its light trail. And given the vast space of the Universe a whispered and thereby dim 'message light' would not reach far if this message was about saying 'Hello, is there anybody else out there?' ...

        Even a message encoded within a Neutrino stream would reveal its source, as its vector of direction is already included in the stream itself and its distance measurable by 'cross bearing' as a form of triangulation - although detecting Neutrinos is a difficult task on its own due to their limited interaction tendency.

        SETI once discovered the so called WOW! signal and the article about it on Wikipedia may give a good insight on how the localization was done and which frequency-band was 'listened' to:


        The only 'untraceable' form of communication my limited fantasy can think of would be based on 'quantum entanglement' or 'quantum teleportation', which by its nature would not make sense for a first 'hello', as those 'quantum conditions' had to be created first and therefore needed to be known and synchronized by both communicating parties. In terms of location spotting this method seems 'save' to me ... :o)


        Trans universe communication is a bit on the frustration side anyway, as our and probably other species are to limited in life-span to really get to enjoy it. So even if we would be able to detect a clear and intelligent message one day, those minds who send this signals on purpose are most likely not existent anymore and maybe their whole species as well ...

        So if there is no 'faster than light' way of communication, our odds are quite limited ...

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