The Davenport-Lewis-Schinzel problem on the reducibility of $f(X)-g(Y)$

Angelot Behajaina, Joachim König, Danny Neftin

We solve the problem of Davenport--Lewis--Schinzel (DLS), originating in the 1950s, regarding the reducibility of $f(X)-g(Y)\in \mathbb{C}[X,Y]$. This yields an almost-complete solut…