Biological network dynamics: Poincaré-Lindstedt series and the effect of delays
Renato Calleja, Pablo Padilla-Longoria, Edgar Rodríguez-Mendieta
TL;DR
This work analyzes Hopf bifurcation in a two-delay, non-diffusive Gierer–Meinhardt activator–inhibitor system modeled as a delay differential equation. It proves the existence of a Poincaré–Lindstedt series to all orders by framing the problem in Fourier–Taylor form, yielding explicit linear recurrences for the-series coefficients and enabling implementation via automatic differentiation. The PL series serves as an efficient initial guess for a collocation-based Newton solver, and together with pseudo-arclength continuation the authors compute and continue branches of periodic solutions across delays. The approach provides a practical framework for analytic and numerical tracking of delay-induced periodic dynamics in biological networks, with potential extensions to diffusion terms.
Abstract
This paper focuses on the Hopf bifurcation in an activator-inhibitor system without diffusion which can be modeled as a delay differential equation. The main result of this paper is the existence of the Poincaré-Lindstedt series to all orders for the bifurcating periodic solutions. The model has a non-linearity which is non-polynomial, and yet this allows us to exploit the use of Fourier-Taylor series to develop order-by-order calculations that lead to linear recurrence equations for the coefficients of the Poincaré-Lindstedt series. As applications, we implement the computation of the coefficients of these series for any finite order, and use a pseudo-arclength continuation to compute branches of periodic solutions.
