They could have tech that makes this less of a inconvenience than it would be for us. If for example if they had some way of hibernating the interstellar travel time, but any sort of help from the home planet would still be decades away, staying put, observing and limited contact would be a possible kind of behavior one might choose.
They would be technologically advanced, but still lack the numbers for any kind of "safe" interaction with us from their point of view.
Perhaps not, and I am highly skeptical of the whole concept of UFOs in general, but I can't prove a negative.
Things like quantum teleportation and entanglement, for instance, are still restricted by the speed of light. Even gravity is restricted by the speed of light - this has been proven experimentally. TANSTAAFL.
United States is doing the same thing with the Quantum age. Do you think the military is waiting around for mainstream science to protect its economy and military from quantum computers? No. They are pioneering it, in secret.
Yes, the science was common knowledge. Berlin scientists first split the uranium atom four years before the Manhattan project even took place. It was common enough that science fiction writers of the time wrote stories about atomic bombs before any bombs were ever built, through extrapolation from established science alone, and Kodak was able to deduce the US was working on an atomic bomb because the radiation from testing fogged up their film stock. That's why there was a race on to be the first to a working implementation of that science, and a working implementation was what the Soviets were interested in. I can guarantee you Soviet scientists already knew what a chain reaction was.
Stop acting like you know what you're talking about, the more you comment the more obvious it is that you don't.
Generational ships, species that require fewer resources to thrive or that have manipulable hibernation abilities (for instance, if they have antifreeze blood like some jellyfish do, then they could theoretically be kept in suspended animation for a long time without aging or risk of boredom), or if they are incredibly long lived compared to humans for one reason or another.
Our best telescopes today can see oxygen in the atmosphere of planets that no living human could ever possibly set foot on regardless of what we did. It's possible that another different civilization could have noticed our planet and sent out a scout vessel 200 years ago just to see if it was a viable alternative planet for them to colonize.
But aside from the fun talk of scifi space travel possibilities, I am also very skeptical of UFOs and alien life forms being close enough to meet us during my lifetime. I would need to see them in person to believe that it wasn't yet another hoax.
If we have to take UFO reports at their word, just for the sake of argument, what is described at the very least appears to have some form of non-reactive propulsion that acts like gravity control. Just them being able to move at high velocities without creating a sonic boom or any visible means of propulsion would put them in the realm of using some kind of weird new physics we don't understand.
"surpassing the speed of light" in 3D, but done in 4-5D is just a matter of traveling a lot less "space", hence you actually didn't need to surpass the speed of light, but you travelled "faster than light", by travelling across the 4th-5th dimension.
Travelling like that could be just like walking 100 yards in the 5th dimension, but in 3D you travelled 100 light years in a matter of minutes (of walking).
maybe you're looking a vessel with more than 3 dimensions, and when it moves throught the next dimension/s, it allows it to do those kinds of movements. Maybe we're just seeing just an "expression" of a 4th-5th dimension vessel in 3D, but it's not really fully interacting with our three dimensions (maybe it's just leaking photons), and that is why those things can make impossible things like instant acceleration, submerging in the ocean at high velocity without making a minimal splash (maybe they could "submerge" into solid ground as well? that would explain UFOs in mountains, if you can get into a mountain to hide your presence, mountains look amazing as amazing parking lots for UFOs).
One explanation (which i can obviously neither confirm nor deny) is that aliens don't come from Far Away, but from neighboring dimensions.
Why?
If I lived for a million years then interstellar travel would be feasible for me with the physics we know.
We have trouble defining "life" in general terms because we only know of this planet. If intelligent life developed (some say it has developed here :-) in the universe then there is no predicting what form it would take.
We may not recognise it, or it us
What Would Sabine Say About This?
She says there might be a chance...