Yes aliens exist but chances of them coming to earth any time soon are slim. The universe is huge, there are probably billions of worlds with aliens who are hundreds, thousands and millions of years ahead of us technologically.
And the reason we haven't see them?
Well there are a few things I can think of:
1. Maybe faster than light travel is hard to do. Sure it's nice to dream of it in science fiction...but how hard is it in reality? Not only do you have to figure out how to travel faster than 671,000,000 miles per second. But then you have to figure out how to build a shield system that has the energy to take abuse of millions bits of space debris hammering at it every millisecond.
2. Even if the aliens had light speed, and hyperspace...you have to ask yourself who would be there to hear us? It's only been ~80 years since the first TV broadcasts....so there are probably only a few hundred stars that the signal reached so far(out of trillions)...and we have no idea about signal distortion...who knows maybe 3 light years from earth, the tv signal can't be discerned from the universe's background noise? Even a thousand years from now, even if the signal remains just as strong as it is on earth, the signal would still only cover an insignificantly tiny portion of the universe.
3. Even if they heard us, if they have light speed, they probably know of thousands other races, making us nothing special....they might get around to sending us a research mission...a few years from now, when the university that found us gets the funding to send interns on a space trip. And if they don't have light speed, it'll take them another 500-1000 years to get here.
Frankly the way I view it, is that on galactic scale we are in the boonies...if there is any big alien empire, it exists near galactic center, where there are hundreds of stars within a small distance.
It's not clear that the galactic center is a good place for life to evolve. The higher stellar density also means more supernova explosions, and there's also the black hole at the center which likely from time to time was a very bright source of x-ray and ultraviolet radiation.
And the reason we haven't see them?
Well there are a few things I can think of:
1. Maybe faster than light travel is hard to do. Sure it's nice to dream of it in science fiction...but how hard is it in reality? Not only do you have to figure out how to travel faster than 671,000,000 miles per second. But then you have to figure out how to build a shield system that has the energy to take abuse of millions bits of space debris hammering at it every millisecond.
2. Even if the aliens had light speed, and hyperspace...you have to ask yourself who would be there to hear us? It's only been ~80 years since the first TV broadcasts....so there are probably only a few hundred stars that the signal reached so far(out of trillions)...and we have no idea about signal distortion...who knows maybe 3 light years from earth, the tv signal can't be discerned from the universe's background noise? Even a thousand years from now, even if the signal remains just as strong as it is on earth, the signal would still only cover an insignificantly tiny portion of the universe.
3. Even if they heard us, if they have light speed, they probably know of thousands other races, making us nothing special....they might get around to sending us a research mission...a few years from now, when the university that found us gets the funding to send interns on a space trip. And if they don't have light speed, it'll take them another 500-1000 years to get here.
Frankly the way I view it, is that on galactic scale we are in the boonies...if there is any big alien empire, it exists near galactic center, where there are hundreds of stars within a small distance.