Are we alone in the universe?
Since I was a little child, I liked to spend hours watching at the blue, infinite sky. A question kept going on inside my head, desperately searching for an answer: 'Are we alone in the universe?'. This is maybe one of the hardest question to answer for mankind, but it's also for sure one of the most debated. The first, spontaneous conclusion that came to my mind was no. Something else had to be in our universe, which is infinite. As consequence there's an infinite possibility that somewhere, in a galaxy far far away (cit.) an alien society is prospering. The reading of some books instead changed my mind. What made me less sure about my first opinion are basically this: the Universe is not infinite. Based on the most convincing theory we came up so far our Universe is expanding at a quite constant rate. This is not only implies that distances are inexorably increasing, making space travels such an utopia, but also nothing is given for sure to exist. The probability of...
