Based on my understanding of physics - nothing can go faster than the speed of light and even approaching the speed of light makes it impossible to fathom the complexities involved - not to mention the killer inertia levels, etc. - means that it is almost impossible if life exists in outer space it is visiting earth - and even if there is life in space able to t ravel between stars - the odds of them finding earth is just as astronomical.
If - if - if UFO's are real - they have several possible origins - humans from the future visiting the past. Time traveling in theory is much easier to do than traveling between stars.
Or
Beings that live another plane of existence parallel to our own - again with the theory being that breaching the dimensional membrane is easier than traveling between stars.
The supposed speed of light problem is reportedly not a problem at all.
Some ‘ET’s’ have even laughed in physicists faces about it. There’s reportedly several . . . technologies, strategies around what turns out to not be a limiting anything.
There’s evidently lots in the physics text books that’s just plain wrong.