In My Time of Dying: How I Came Face to Face with the Idea of an Afterlife

by Sebastian Junger

Because quantum physics could be tested without being understood, it allowed humans to see how the universe worked without knowing why. At that point, physics was so abstract that it bordered on a kind of mysticism. For two hundred years, scientists trusted that the physical world could be understood because it could be measured, but in 1927, Werner Heisenberg demonstrated that subatomic particles changed behavior when observed. That led to staggering questions of whether matter—and reality—was ultimately even knowable. Schrödinger both clarified and deepened the issue by showing that electrons—the foundational unit of existence—were just a series of probabilities that only “collapsed” into one state when measured by humans.