The relationship between a strip Wiener--Hopf problem and a line Riemann--Hilbert problem

Abstract: In this paper the Wiener--Hopf factorisation problem is presented in a unified framework with the Riemann--Hilbert factorisation. This allows to establish the exact relationship between the two types of factorisation. In particular, in the Wiener--Hopf problem one assumes more regularity than for the Riemann--Hilbert problem. It is shown that Wiener--Hopf factorisation can be obtained using Riemann--Hilbert factorisation on certain lines.