What do you guys think of UFO's?

[The chaser]

Given all that. The possibility of us seeing an alien is 0,00000000000001%

Is a 0,00000000000001%, but there's still a chance, in a 5.000 millions of years, when the sun dies, we would already meet an alien. They are there. Even if they didn't arrive here because they wanted so.

And, we are searching planets with life, why couldn't the aliens do so too?

I've also readed a very interesting thing: A cientist (who's name I don't remain ) explained that the space is like a paper. If we fold that paper, two parts of the paper would collide, making a portal.

It's a weird theory, sorry if I explained myself wrong.