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Once we have granted that any physical theory is essentially only a model for the world of experience, we must renounce all hope of finding anything like the correct theory... simply because the totality of experience is never accessible to us.
Hugh Everett

The truest acts of scientific brilliance come from those who push the envelope of conventional wisdom

I figure SETI is looking for accidental as well as "Earth-directed" communications, like leakage from whatever the ETs have for television. If we catch one such signal, we would try to intercept more of the same signal, or more signals from the same direction, attempt to decipher it (assuming it's not truly encrypted, just a strange protocol), and learn what we can about them. What we learn could have an effect on society--if we learn of technology new to us (possible even if they are at a similar level of development), or get new forms of entertainment even. I suspect most changes would be positive. I suspect it WILL get more kids interested in science. It might not do much for the space program as interstellar travel is way too far in the future. The fringe groups will still be fringe groups, just with different crazy beliefs. Some will read more into alien lifestyles than there really is (just as Einstein's Theory of Relativity resulted in philosophers saying stupid things like, "By Einsteins Theory of Relativity, the political situation depends on your point of view".)

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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

Quidquid latine dictum sit, altum sonatur.

personal page: http://blog.astrosketches.info

Any communication from so far away would become so diffuse as to become meaningless and undetectable within back ground noise.
Given that, and assuming that you recieved a narrow beam of data for a
few hours ....(just to play with) it wouldn't maen anything, just like if you recieved a beam of telemetry data . Interesting noise.
Best regards, Dan

Hence the term “to ponder”. What do you think the Earth’s reaction would be? Let us recall that there are many ways that we communicate to each other. Yes, some are crude or inefficient and some are much more creative and possibly efficient. Lasers have been around for almost 50 years and let’s remember that the theory for the laser was around over 40 years before that. Also after reading some of what the Russians have managed to do in their research on radio communications (Radiophysics and Quantum Electronics ISSN 0033-8443) it might be challenging yes but not impossible. Besides, even if we did manage to as you say “receive a narrow beam of data for a few hours” do you actually think that would be the end of it? Given enough and the right kind of motivation we’d do whatever it took to get “hooked up” (as it were).

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Once we have granted that any physical theory is essentially only a model for the world of experience, we must renounce all hope of finding anything like the correct theory... simply because the totality of experience is never accessible to us.
Hugh Everett

The truest acts of scientific brilliance come from those who push the envelope of conventional wisdom

If the signal came from M31 then we should have nothing to fear because the signal took 2 million years to reach us - so if they haven't dropped in by now (given 2 million years of additional development) then it would seem unlikely that they would ever do so.

And IIRC current technology can't detect "routine " signals even from nearby stars:
IOW, SETI is looking for a signal which is meant to be found - kind of like an EM galactic beacon or "lighthouse." They aren't looking for signals that say "we're running low on Pampers, please send a load on the next hyperjump."
http://www.seti.org/about-us/faq.php#a3
But would such detection spin up new lines of research? Almost certainly. First order of business would be improving radio technology so we could find the "rest of the message" and maybe send back a response.

Cryptography would also see lots of funding so we can try to decipher the message.

Hi, And I suppose that you will be willing to wait for a response for....
say.......76 years. Hmmmm.....
Dan

Assuming it could be proven not to be some kind of hoax it would be one of the greatest discoveries ever - positive proof of the existence of other intelligent life.
For practical effects, I expect there would be an enormous increase in interest in radio astronomy and if the aliens appear to be venturing into their own solar system I expect it would be a shot in the arm to the space program too.
But beyond that, I think having aboslute knowledge that there is other intelligent life would change our entire worldview as a species in much the same way the worldview of isolated human communities like the American Indian and the Australian aborigene were shattered and re-arranged by contact with Europeans.

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"You miss 100% of the shots you don't take" - Wayne Gretzky

From the Andromeda Galaxy?? That's even less likely than finding life in our own Galaxy.

A few things, but all of them relevant to the possible impact:

1.) Distance: If the signal origin is extremely distant, say hundreds or thousands of light-years, then the effect will be minimal. If the origin is much closer, within a few dozen or a couple of hundred light-years, then the societal impact will probably be greater.

2.) Persistence: If the signal is short but unambiguous, then the effect will be much less than if it is long or continuous.

3.) Richness: If the signal is unambiguous but contains no real information (e.g., an intercepted radar beam), then the effect will be less than if the signal clearly has significant embedded data, whether we can decipher it immediately or not.

In sum: a close, continous, data-rich source will probably have an enormous societal impact. A distant, transient, data-poor source will make waves only in the science community.

So, what if it were a grade-A signal? I personally am skeptical of any long-term effects beyond the initial whirlwind of results--again, outside of the science community. One hundred years ago, people would've been flummoxed by the idea of supersonic jets and space probes; today, it's no big deal. I think even something as radical as detecting another species could eventually be taken as a matter of course by some, and simply ignored by others.

The only situations in which I think the effect would not be so forgettable would be if the signal indicated either a potentially hostile race, or one that could provide us with useful information (in which case, of course, it probably wouldn't be an accidental interception).

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"Call me old-fashioned, but I think fire is magic. And it scares me a lot."

--The State

From a dozen lightyears away would be "ridiculously far away" enough. And remember that whatever level of technology they're at at the time of transmission would be out of date by the time we received any radio message. For the Andromeda Galaxy, two and a half million years will have passed.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
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Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

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Once we have granted that any physical theory is essentially only a model for the world of experience, we must renounce all hope of finding anything like the correct theory... simply because the totality of experience is never accessible to us.
Hugh Everett

The truest acts of scientific brilliance come from those who push the envelope of conventional wisdom

I would argue that we accept things like supersonic jets as "no big deal" precisely because our society has changed. The discovery of extraterrestrial intelligence would fundamentally change our worldview. Sure in a few years we might think it's no longer a big deal, but that would be because we had changed.

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"You miss 100% of the shots you don't take" - Wayne Gretzky

Consider this though, if the "ridiculous" distance is "only" a few dozen light years, even though radio transmissions will effectively take a generation to go back and forth, there's another part of the spectrum that could be far more revealing immediately; optical. I'm sure it would spur the development of much larger interferometry-based space telescopes designed to directly image terrestrial planets conducive to familiar forms of life. Imagine being able to directly image a planet out there known to host life. Perhaps within another generation we could construct such a large series of space telescopes that we could directly observe any possible large structures they have in orbit of their planet, their star, or cities on their world. By the time the first "return" message gets to us, perhaps we could have already learned a great deal about their development. The side benefit of being able to directly study other nearby terrestrial worlds with the same array would be incredible.

We might be lucky and see them launch their invasion fleet.

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LOL . My aren't we up late? I going to bed, and You just getting up perhaps?
So long, and make it a good day.
Dan

I would argue that we accept things like supersonic jets as "no big deal" precisely because our society has changed. The discovery of extraterrestrial intelligence would fundamentally change our worldview. Sure in a few years we might think it's no longer a big deal, but that would be because we had changed.

Good point.

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"Call me old-fashioned, but I think fire is magic. And it scares me a lot."

--The State

What a powerful and awe-inspiring idea First Contact is.

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"If you think the LHC will create black holes, you might as well believe Hobbits are at the bottom of your garden."- Dr. Mike Inglis
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"Carl Sagan sent a message to ET,
Neil Armstrong walked in the Sea of Tranquility
Steve Squyers built Spirit and Opportunity
Dan Haylen upchucked in zero gravity." -Brent Simon, The Space Camp Song

"Tonight on Krang..." hahaha

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