100 Unanswered Questions About Ourselves, Our World and Our Universe

100 Unanswered Questions About Ourselves, Our World and Our Universe: Top Scientists were asked about 100 unsolved problems in their fields. They sent back provocations — on the origins of life, the possibilities for human progress and much more. By Bill Wasik Bill Wasik is The Times’s science editor. This is the first of a series called Unknowns, about unanswered scientific questions. Are you