A couple of points my friend. 1) The eclipses of the sun noted in the article were determined to be too regular to be any of the possibilities you note. There may be a natural phenomenon that explains the information gathered but none the scientists could conceive fit. 2) Yes a Dyson structure is speculation but it is closest to fitting the observations so far. They ARE NOT claiming anything beyond that. 3) Assuming we have sampled enough of the spectrum for long enough (less than 60 years) or covered enough of the vast area in our neck of space to have any idea what is out there is ludicrous. 4) Whether we are the only sentient beings in the galaxy or universe is the rankest of speculation. Just basic math and probability theory would argue against that. 5) Regardless it may be that whatever is out there no matter how advanced, we may never know. It may be that ole Albert was right and we'll never be able to travel faster than light effectively. If so we and all other civilizations (if there are any) are ants on islands in the middle of a vast ocean.
I told you fellers, if you think a bunch of Egyptian slaves built those pyramids all by themselves. .. take a look at their drawings on the wall, those don't look like people.
Even assuming that Einstein was right doesn't preclude the possibility that a much more advance form of life hasn't figured out how to traverse the universe in was that we are not even capable of imagining. I read just a few weeks ago that physicists had succeded in creating a wormhole in the lab. They were only able to transport a subatomic particle but transport it they did. Who knows how far science can advance that in many years to come.
This is a controversial point and they seem to be finding a fit where they want to. It is far more likely to be a natural phenomenon, since 100% of what we have ever observed throughout history has been a natural phenomenon or of our own creation. They have not proven this hypothesis by any means. And even the science fiction concept of a gigantic space web is a piece of infrastructure that is impossibly large. The costs and material would be be, well . . . astronomic. Science fiction is fiction, mon ami. I think I said that more succinctly.
