Your ‘Where I Work’ series (see, for example, Nature 580, 158; 2020) reminds me that travel itself can be scientifically productive. Travel can free the mind from its routine tasks, opening it up to new ideas. The polymerase chain reaction, for example, came to the late Kary Mullis while driving late one night from Berkeley to Mendocino in California. A lynchpin in today’s screening of thousands for COVID-19, it earned him the Nobel Prize in Chemistry in 1993.

Other Nobel-worthy ideas seeded on the move include Subrahmanyan Chandrasekhar’s insight into the maximum mass of a white dwarf star, and John Robert Schrieffer’s mathematical description of the ground state of superconducting atoms. Chandrasekhar was on a ship from India to England when he had his brainwave at the age of 19; it won him the Nobel Prize in Physics in 1983. Schrieffer’s came to him on New York City’s subway, earning him a Physics Nobel in 1972.

Imagined travel, too, has contributed to discoveries. A notable example is Albert Einstein’s 1907 ‘elevator’ thought experiment, which inspired his general theory of relativity. Another is mentioned in Dante Alighieri’s The Divine Comedy, when the poet describes Galilean relativity in the context of flight on the back of a monster (L. Ricci Nature 434, 717; 2005).