[TaupeRanger]

None of those things are impossible based on known physics. Traveling backwards in time to observe the beginning of the universe, and/or somehow existing outside the universe in order to do the observation, is impossible. Could we learn new physics that make it possible? Yes, but it is still a totally different class of problems than the ones you listed. Those were ONLY a question of knowledge. The problem at hand is a question of both knowledge AND the laws of physics actually allowing for that knowledge to be had. There was never any reason to assume that we would be unable to cure a certain type of cancer with the right knowledge alone.