Nonlinear DNA dynamics: Nonlinearity versus dispersion

In the present paper we study the impact of dispersion and nonlinearity on DNA dynamics. We rely on the helicoidal Peyrard-Bishop model and use the fact that nonlinear DNA dynamics represents an interplay between nonlinearity and dispersion. We state that a dispersion coefficient P and a coefficient of nonlinearity Q, existing in nonlinear Schrödinger equation, are mutually dependent and show how function Q(P) and P(Q) can be obtained. Also, we show how all this can be used to find a possible interval for the parameter describing helicoidal structure of DNA.