Curiosity-driven research has long sparked technological transformations. A century ago, curiosity about atoms led to quantum mechanics, and eventually the transistor at the heart of modern computing.

When scientists unwittingly turned helium into a superfluid — a feat many thought was impossible — Dr. Leggett not only recognized what had happened but also explained how.

Thanks to the alternating single-double nature of the bonds, electrons in these orbitals end up delocalized; the differences between the bonds become a bit irrelevant, and the molecule is best viewed ...