Stopping the Universe's Death
As often as Isaac Arthur brings up the science fiction writer Isaac Asimov I am surprised Isaac Arthur didn't mention the short story "The Last Question" in this video. Just sayin'.
Far in the future a civilization, possibly existing as artificial intelligence inside a planet-sized computer; completely alien from Earth, will have a problem. The Universe is slowly losing usable energy due to entropy. Maybe nothing can be done about it. Maybe it will turn out over billions of more years of scientific progress a way will be found to reverse entropy on a cosmic scale. Maybe the expansion of the Universe will slow or stop altogether. Maybe another "Big Bang" restart will happen. All these possibilities are presented in the video. Another possibility of utilizing other parallel universes or dimensions was also discussed. My personal favorite would be inventing time travel and going back in time to a younger Universe.