Are we looking for the right signal?


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Message boards : SETI@home Science : Are we looking for the right signal?

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Profile TheGoose
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Message 1024157 - Posted: 10 Aug 2010, 11:50:36 UTC

Some time ago I watched a Discovery documentary in which the big-bang theory was explained as being true because of the residu of radiation. The high-frequent lightflash of the big-bang slowly changed into infrared-light of lower frequentie that subsequently changed into radio interference. Because this kind of radiation was found proof was found for the big-bang theory.

This being the case.

Should we or are we looking for radiation with right frequency? If ET is transmitting audio or video signals, isn`t it true that they also detereorate or change over time/distance into signals with a lower frequency (kinda like the signals submarines use) and are we also Boincing these signals?

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Profile William Rothamel
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Message 1024239 - Posted: 11 Aug 2010, 17:08:05 UTC
Last modified: 11 Aug 2010, 17:10:18 UTC

Yes, a mystery here for sure. Seti allows for a doppler shift around the Lyman Hydrogen line due to the orbital velocity of a planet that might be transmitting and possibly our own orbital motion or motion thru space. There would also be a red shift due to galaxies that are receding from us and a Blue shift from those approaching us. As for the frequency shifting due to lost energy that doesn't seem to come into play--apparently e= h x lambda ignores the amplitude of the wave. In the doppler shift it would be energy reduction per unit time--total energy still the same ??

Sort of a puzzlement to me and I have taught physics.

It seems that there is no tired light effect due to frequency change to account for loss of energy as light travels. Apparently the vacuum is a super-conductor for light or photons.

Relative velocity may be an issue here. We have orbital velocity, spin velocity, orbital speed around the galaxy, recession speed due to expansion of space and galactic speed as well--AND so does the potential sender of info to us.

Might be time to add these up and see if our window is wide enough==probably is from those whom we think are close enough to hear.

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Message 1024253 - Posted: 11 Aug 2010, 18:15:10 UTC

all the more reason to nudge this forward, and try to reach some conclusions. An answer of "no not like this" is still an answer, and much has spawned from
this method.

The answer also could be "not yet, let us keep looking" or "ah there they are."

Or there could be more undiscovered layers under this onion.
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Message 1024326 - Posted: 12 Aug 2010, 20:29:04 UTC - in response to Message 1024157.

... The high-frequent lightflash of the big-bang slowly changed into infrared-light of lower frequentie that subsequently changed into radio interference. ...

This being the case.

Should we or are we looking for radiation with right frequency? If ET is transmitting audio or video signals, isn`t it true that they also detereorate or change over time/distance into signals with a lower frequency...?


Very good question!

For very distant (highly doppler shifted) signals, then indeed we may be looking at too narrow a band for our present search assumptions.

However, very highly doppler shifted signals due to distance will also be signals that are very weak due to the inverse-square law of power reduction over distance... Also those sources will be from a very distant past due to the time of travel.


I would suspect that the present search parameters are a good compromise so that we only search a broad enough doppler shift to be able to catch signals from sources that are close enough to detect. There is no point in searching for a very high doppler shift if you expect the corresponding distance to be too far to be able to detect any meaningful signal.


Hope that goes some way towards an answer :-)

Keep searchin',
Martin

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Message 1024372 - Posted: 12 Aug 2010, 22:25:53 UTC - in response to Message 1024326.

not a good enough answer yet.. so onward we go.

Have we found ET?
How many have we found/not found?
Are they bringing cupcakes?

Then, and only then will I be satisfied.


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Message 1024605 - Posted: 13 Aug 2010, 18:00:46 UTC - in response to Message 1024372.

not a good enough answer yet.. so onward we go.

Have we found ET?
How many have we found/not found?
Are they bringing cupcakes?

Then, and only then will I be satisfied.



So near and yet so far - see http://www.youtube.com/watch?v=h9eX7URM_hU
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