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arXiv · 2408.06548

The strong unstable manifold and periodic solutions in differential delay equations with cyclic monotone negative feedbck

Anatoli F. Ivanov·Bernhard Lani-Wayda
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Abstract

For a class of $(N+1)$-dimensional systems of differential delay equations with a cyclic and monotone negative feedback structure, we construct a two-dimensional invariant manifold, on which phase curves spiral outward towards a bounding periodic orbit. For this to happen we assume essentially only instability of the zero equilibrium. Methods of the Poincaré-Bendixson theory due to Mallet-Paret and Sell are combined with techniques used by Walther for the scalar case $(N = 0)$. Statements on the attractor location and on parameter borders concerning stability and oscillation are included. The results apply to models for gene regulatory systems, e.g. the `repressilator' system.

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Anatoli F. Ivanov, Bernhard Lani-Wayda. 2025-03-29. The strong unstable manifold and periodic solutions in differential delay equations with cyclic monotone negative feedbck. https://arxiv.org/abs/2408.06548

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