Martin David Kruskal, a mathematician whose work on the properties of an unusual type of wave helped pave the way for fibre-optic technology, died on December 26. He was 81.
Kruskal died in Princeton after a series of strokes. His death was announced by Princeton University, where he spent 38 years on the faculty before moving to Rutgers University in 1989.
Kruskal’s best-known advance came in the 1960s when he was able to use equations to explain a phenomenon first recorded in 1834 when Scottish scientist John Scott Russell noticed a bump of water travelling through a canal near Edinburgh. On his horse, Russell followed the bump for about 3km.
Usually, waves that collide deform each other. But this other kind, which Kruskal and collaborator Norman Zabusky came to call ”solitans”, do not; instead, they pass through one another. Light transmitted over fibre-optic cables for communication purposes has the same properties.
For his work on solitans and other issues in math — including using the theory of general relativity to help explain black holes, Kruskal was given a National Medal of Science in 1996 and the Steele Prize for Seminal Contribution to Research by the American Mathematical Society last year, among other awards.
He first came to Princeton in 1951 to work on a then-classified project to produce controlled thermonuclear fusion. He was later a professor of astronomy and then held a chair in applied and computational mathematics before becoming a professor of mathematics in 1979.
Another of his legacies, which is better known among magicians than mathematicians, is the Kruskal Count, a card trick that employs some deceptively simple math to make it seem like the magician is reading the mind of a subject who picks a number between one and 10. — Sapa-AP