>>12354723>What's the most convincing hypothesis for why extraterrestrial intelligent and technology life may or may not exist in the Milky Way?The Galaxy is huge and we can see very little of what it looks like *today*. See that small circle? Of all that Humans can see and detect with our radiotelescopes, what is inside the circle is what happened in the past 200 years. We can stipulate, with a high degree of certainty, that there are no advanced alien civilizations within that small circle, because we have not seen biosignatures, evidence of advanced craft or megastructures inside the circle.
As for the rest? We are looking at things that happened 500, 1000, 10,000, 50,000, millions, billions of years from now.
So there could be advanced aliens that achieved spaceflight 300, 500, 1000, 5000 years ago jetting around the Galaxy and we would have no way to detect them if they are outside our "range".
This also means aliens would not be able to detect our civilization so easily either. Biosignatures on Earth would be detectable from 500 million light years away, but signs of our civilization (such as artificial lights, industrial chemicals on the atmosphere, radio waves, etc.) could only be detected from 200 light years away (the circle) since that's roughly when we started emitting those.
