Yes there's a chance that the laws of physics are somewhat different to what we understand today. Unlikely given that the greatest minds have still not seriously broken Einstein's theories in over a hundred years. All of these ideas about wormholes and warp drives are certainly convenient for SciFi writers and make some excellently entertaining movies but even if such things are possible these advanced civilisations would still have little or no reason to come here and then simply fart about and hide in caves....
There are unexplained objects out there, but they remain unexplained. It’s a big leap to say that they are extraterrestrial. We don’t know everything about our own planet, or about conditions or our own existence come to that.
I would imagine over time what we believe to be true will be found to be inaccurate at best. It may not be in our lifetime but almost everything ever believed in the past has been proven inaccurate.
Why do we go on holidays abroad in spite of not fully exploring the u.k? Why do we look to the Skies in spite of not mapping the oceans and the land? We miss what's under our noses all the time. I'm not saying there is anything there but we're always in such a mad rush to dismiss everything.
oh yes, I’m not saying aliens have been here or haven’t, or could get here or couldn’t. I don’t know, but it would be the most spectacular discovery of all time to find intelligent life somewhere else (finding it on earth or in Sheffield would be good enough sometimes). It does seem odd that you would travel for light years to get here then just molest some mid West Americans and their cows before leaving