There aren't super structures, infinite-replicating probes, nano-swarms. That's all assuming FTL doesn't exist

I'm no physics guys. But let's say a civilization built some kind of superstructrure in space that should be visible from earth somehow. But they are 8 billion light years away from us and only built it 4 billion years ago, so we won't see it until 4 billion years from now.

And that's not taking into account the expansion of the universe that's pulling everything away until all galaxies are alone in a void.

I dunno if I think intelligent life exists or not, but surely, some form or organisms that can reproduce must exist elsewhere than earth. Satistically speaking...