TITLE: What properties of knots lead Lord Kelvin to hypothesize that atoms were knots in the ether?
QUESTION [14 upvotes]: I've often heard that Lord Kelvin was one of the first people to study knot theory, as he hypothesized that atoms were knots in the ether. I assume that he had some compelling evidence for this fact.
What properties of knots did Lord Kelvin consider similar to atomic properties?

REPLY [2 votes]: It wasn't just Kelvin---the three premier Scottish physicists of the 19 th century, Maxwell, Thomson (Kelvin) and Tait were all fascinated by knots.  Some details can be found in the article by D.S. Silver "Scottish Physics and knot theory's odd origins" which is available online. The fact that this didn't lead to important advances in physics should not blind one to their other seminal contributions and it is arguable that this work led to the development of modern knot theory.