Bristol physicists break 150-year-old law

By “break a law,” of course, they mean “find where the law doesn’t apply”. Can’t break a law when you’re in a jurisdiction that doesn’t have that law.

In 1996, American physicists C. L. Kane and Matthew Fisher made a theoretical prediction that if you confine electrons to individual atomic chains, the Wiedemann-Franz law could be strongly violated. In this one-dimensional world, the electrons split into two distinct components or excitations, one carrying spin but not charge (the spinon), the other carrying charge but not spin (the holon). When the holon encounters an impurity in the chain of atoms it has no choice but for its motion to be reflected. The spinon, on the other hand, has the ability to tunnel through the impurity and then continue along the chain. This means that heat is conducted easily along the chain but charge is not. This gives rise to a violation of the Wiedemann-Franz law that grows with decreasing temperature.

… because you have found conditions where the law does not apply. So: neat science. Predictable behavior from the title editor.