> fundamentally misunderstand physics Keep in mind that we think we know how to reach a destination faster than light (although not travel faster than light).

> fundamentally misunderstand physics Keep in mind that we think we know how to reach a destination faster than light (although not travel faster than light). We just don't know how [edit: to build the engine] or even if it's a practical approach. What it shows is that physics does allow us to reach a distant star and return in a single lifetime. > inconceivably long lived I'm not sure about this one. That species would have had to evolve somehow, unless they solved the mortality problem or unless Earth-like evolution is not universal. Even if they could, given the timeframes, why would they visit? My point is that, yes, we don't have enough evidence to abandon possibility #3. We also don't have enough knowledge to abandon possibility #1 and #2. That being said, I'd wager that if ET has visited Earth less than 1% of the sightings are authentic - we aren't that interesting.