[Diggity]

The answer is obvious. We are just not advanced enough yet to see what they have done.

Have you ever considered that we are an artifact of some advanced civilization?

We don’t even know what gravity is yet. We are primitive beyond description compared to a race a million years ahead of us.

John

[MHGinTN]

You raise an cogent point. Now, Dr Ross used a similar approach, only he went back in time a million years to see what the conditions would be like, then 100 million, then 500 million years. It is very likely that gamma ray bursts actually contributed to the beginnings of life evolving on Earth. BUT, if you go back too faqr from our 'quiet zone' of approx 500 million years, the universe in our own galaxy is too violent, and if opne goes back to the period during which the star in the article exploded, well, the size of the universe and the numerous events like this star death make the universe as a whole much less capable of sustaining life on a planet. If one applies the Drake approach back 500 million years ... so my 62 years old brain is tired and I'll have to stop this exercise for now.

One last thought for you: we think in terms of space stretching out and offering a buffer to the past, as in the past violent events such as this star, but what we ought to consider occasionally is the temporal expanse which gives us the protection for our 'quiet period' of life development on earth. And that doesn't even touch the notion that dimension Time may have volume, as well as planar present, and linear past.

[Centurion2000]

We are just not advanced enough yet to see what they have done.

Stellar Engineering projects would be obvious to us even now. A ringworld, dyson sphere or any matrioshka sphere would be obvious if the start itself is in detection range.

Sorry, I'm not even going to consider the Danikenite hypothesis without a shred of proof.

A race one million years ahead of us technologically would have already started reorganizing the galaxy / universe to better suit them. It would be staggeringly obvious if they started doing things like that.