I wish I'd read this whole thread before posting. It seems that serious and interesting discussions are no longer possible in this Forum.
I'm sure I've voiced this opinion before but I can't remember which forum it was so I'll pose the questions and my beliefs again:-
1. IF aliens had the techology to travel thro' space why would they pick on an insignificant planet orbiting an insignificant star in one of billions of galaxies?.
2. WHY do all the "alien" sightings consist of beings veryt similar to the human fo ...[text shortened]... back in time.
They only have to work out how to do it and dodge the "grandmother paradox" somehow.
Oh well! I'll accept it as it is.
I tend to think similarly.
The infinite vastness of space renders light-speed as an incompatible barrier for efficient, timely travel using the traditional "point A to point B" model.
An intriguing possibility is the existence of a "wormhole" or an "inter-dimensional portal".
A rip or tear in "space-time" is said to be theoretically possible. During the peak of nuclear weapons testing, could such a portal have been created and used for exploratory travel by an extraterrestrial intelligence? I suppose it's possible.
Additionally, quantum theory at least suggests the possibility of parallel universes. Could an advanced intelligence have already discovered a work-around?
They've had 13.6 Billion years in this universe to work it out. 🙂