A couple of Canadian astronomers say that they have found periodic signals coming from roughly 200 stars out of millions in the Sloan Digital Sky Survey data. They say that they have eliminated earthly interference and a variety of other possible causes. Their paper is published in the Publications of the Astronomical Society of the Pacific. And interestingly, most of the 200 stars are similar in spectral type to the Sun. The SETI people expressed skepticism but say that they will follow it up. The full-text of the paper is here: http://iopscience.iop.org/article/1...D39C1C4BFD8E4EF475E.c2.iopscience.cld.iop.org I haven't read the entire paper, just the abstract summary and the conclusions. What's more, I probably lack the expertise to form an informed judgement of it if I did. But my initial response is that these astronomers hypothesized a small set of possible explanations for their data, one of which was extraterrestrial intelligences. They proceeded to eliminate all of the hypotheses in their set except for ETI's, and concluded that it must be ETIs on that basis. This is basically the same philosophical issue that Wegs raised in the inference to the best explanation thread (before it went off the rails). If there are only a handful of competing hypotheses to explain some observations, and all the hypotheses but one seem to be eliminated, then the remaining one would be the best of the bunch. But that doesn't mean that it's the best in general, that it's the best of all possible explanations. The problem is that there may be all kinds of additional hypotheses that nobody has even considered that might better explain the observations. So I'm inclined to think that these astronomers are probably reaching when they conclude that the periodic signals come from ETIs. They should be saying that the cause of the periodic signals is currently unknown. Which raises the question, how can SETI researchers ever be sure that they have excluded all possible alternative explanations and really are detecting ETI's?
Aren't they green?? I believe Earth is the first planet created and the centre of the universe so aliens will not be found on other planets. Doesn't stop me wanting to go there.
It says sorry this page is not found when i try to go to your link. Also why is this not a big news if its true.
Indeed. This is why I never liked Holmes' famous assertion about eliminating the impossible. It only works if the set of choices are a known, closed set. His quote really should be "Once you have eliminated the impossible, the only thing remaining - no matter how unlikely - is ... everything else you haven't thought of yet." Or, as Rumsfeld said "There are unknown unknowns."
