In a recent paper published to arXiv, the physicists Roland Allen and Suzy Lidstrom, of Texas A&M and Uppsala University, respectively, tackled the question about the Question by describing what they believe to be the 42 ultimate questions of life, the universe, and everything.

In a homage to ‘Hitchhiker’s Guide to the Galaxy,’ two physicists explain the biggest unknowns in science. I’ve summed them up as a tweetstorm.