I think there could be several reasons. Some mentioned in the piece.
But it may also be that advanced civilizations are using communication technology that is well beyond our ability to detect.
If some advanced races are space faring, they would need to be able to communicate over the vast distances in real time. That would have to be technology that is faster than light. Maybe something that works in a similar way as quantum entanglement. That's where entangled particles have an immediate effect on one another regardless of distance.
We wouldn't have the technology to detect or decipher such communications.
They could be talking all around us and we'd be deaf to it.
It may also be intentional. They may not want to contaminate us. Much like we take care not to disturb primitive tribes in remote parts of the jungles in South America.
From past experience, we've learned that contact generally goes badly for those societies. Like the way Europeans devastated Native American culture.
In short, I think they're there, and I think they're aware of us, but they're keeping their distance.
There isn't anything we have here that they couldn't get from millions of other uninhabited worlds, so there's really no practical reason to make contact. Study... From a distance, yes.... But not contact.
Posted 579 day(s) ago