## What's our end point, realistically?

Message boards : SETI@home Science : What's our end point, realistically?
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Dr. Walker

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Message 1906455 - Posted: 11 Dec 2017, 18:59:12 UTC

First Post disclaimer! Also, I am not a mathematician nor a physicist. But I'm interested enough to contribute modest CPU time to the effort, and curious enough to wonder, once we have some Southern Hemisphere data points of course, when can we say that we have 80% certainty (based on random assortment probabilities, granted), or 90% certainty, or 99% certainty, that there are no signals to find? (Umm, yeah, finding a signal moots this question.)

Thanks! Until then, crunching happily away,

Scott
ID: 1906455 ·
Gary Charpentier
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Message 1906467 - Posted: 11 Dec 2017, 19:40:25 UTC - in response to Message 1906455.

First Post disclaimer! Also, I am not a mathematician nor a physicist. But I'm interested enough to contribute modest CPU time to the effort, and curious enough to wonder, once we have some Southern Hemisphere data points of course, when can we say that we have 80% certainty (based on random assortment probabilities, granted), or 90% certainty, or 99% certainty, that there are no signals to find? (Umm, yeah, finding a signal moots this question.)

Thanks! Until then, crunching happily away,

Scott

Unfortunately we don't listen to the whole sky all the time. We take random samples from random places in random frequency bands. ET may not be transmitting all the time. ET may be using a weak signal. Hard to put error bars on that. If you assume that ET transmits all the time in a frequency we are looking at and loud enough to hear then you have something to put into equations and that would be when the entire sky is observed twice.

Also remember the size differences of the dishes, it makes a big difference is how weak a signal we can detect. So where Arecibo, the biggest dish can point we see much farther out. With our luck ET is just a light year to far away to be heard.

There may be some formulas in the science papers for this, put in your own assumptions for ET and come up with your own guess as to how long we need to search before we quit. I'd expect on the order of a century or two at least.

Gary
ID: 1906467 ·
Dr. Walker

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Message 1906625 - Posted: 12 Dec 2017, 4:57:45 UTC - in response to Message 1906467.

Interesting! And yes, it's that formula I'm looking for, because I think we maybe can already set an upper limit to the Drake equation. and MAYBE we're within a generation of saying, "None found, size of sample allows 99% confidence that none now will be found." In which case, if we survive, WE would be "the elder race" that sci-fi often posits to save our bacon. Do you know of any of the science papers in particular that might address this? Thanks!

Scott
ID: 1906625 ·
Bob DeWoody

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Message 1906643 - Posted: 12 Dec 2017, 7:46:12 UTC

Then there is also the possibility that ET is out there and knows about our violent ways and they are actively avoiding giving us any clue that they are there in self preservation. Even if the search continues indefinitely without detecting any evidence of ET it would be wrong to assume we are alone.
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
ID: 1906643 ·
Kafo

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Message 1906766 - Posted: 13 Dec 2017, 16:58:40 UTC

ID: 1906766 ·
Bob DeWoody

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Message 1907158 - Posted: 15 Dec 2017, 2:50:48 UTC - in response to Message 1906766.

+1
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
ID: 1907158 ·

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Message 1908313 - Posted: 21 Dec 2017, 10:51:08 UTC - in response to Message 1906455.

First Post disclaimer! Also, I am not a mathematician nor a physicist. But I'm interested enough to contribute modest CPU time to the effort, and curious enough to wonder, once we have some Southern Hemisphere data points of course, when can we say that we have 80% certainty (based on random assortment probabilities, granted), or 90% certainty, or 99% certainty, that there are no signals to find? (Umm, yeah, finding a signal moots this question.)

Thanks! Until then, crunching happily away,

Scott

I think once we are ready....they will beam a massive signal at where ever our radio scopes are aimed..so it does not matter where we are looking to be honest.
The main thing is that we are looking......its all about intentions...:-)
ID: 1908313 ·
Stargate (S.A.)
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Message 1908742 - Posted: 24 Dec 2017, 4:36:49 UTC
Last modified: 24 Dec 2017, 4:37:56 UTC

My hope is to know whether we are just a fluke in how we evolved, had we not got side swiped by something large enough to create the moon "would we be here crunching"?
Maybe if there is life out there might be possible they are in the same boat as us, like shift workers in our daily lives our signals may have missed each other in the crossing, Could it be the wrong signals we are searching?

It's hard to believe that we could be the only ones searching for answers..

Just my 3 cents worth :)

Steve

P.S. I'll keep crunching
ID: 1908742 ·
Bob DeWoody

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Message 1908920 - Posted: 25 Dec 2017, 17:24:58 UTC - in response to Message 1908742.

Stargate, your questions are pretty much the same as those who have been and will continue to probe the universe looking for answers. I, for one, don't believe there is a grand plan, I think along the lines that s*#t happens according to the laws of physics and event unfold pretty much at random. The universe is so big and there are so many stars that even if by random chance there are still thousands, maybe millions of other inhabited worlds scattered throughout the cosmos. But it is also most probably true that the spacing is so vast that it is extremely unlikely that we will ever make contact with any of them.
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
ID: 1908920 ·
Ewan Robertson

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Message 1909527 - Posted: 30 Dec 2017, 1:27:52 UTC
Last modified: 30 Dec 2017, 1:30:32 UTC

Once A.I steps in this will become very fast in the data processing stage i would hope. Google are using it with NASA for the smaller planets that have been missed by the researchers.

There would be a time frame when an alien species will use radio to communicate but it will eventually be replaced by another more technically advanced means... so we would have that time frame to look for it, 200 years - 1000 years who knows. You would imagine that every intelligent species will have to go through this age. So you would think a signal will be picked up at some point with all the planets out there.

Has there been a test to see if the radio signals actually travel that distance and still maintain a strong signal... could they not use voyager (I think) one last time and listen to earth and see if it hears anything and send the data back, i believe it is out of the solar system now and would be a good experiment to try if it has the capabilities to do so that is. It would show what kind of signals to look for also.

Seti would have to be operational all the time.

Cheers
ID: 1909527 ·

Message boards : SETI@home Science : What's our end point, realistically?

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