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arXiv · 2012.05005

Multi-Delay Differential Equations: A Taylor Expansion Approach

Philip Doldo·Jamol Pender
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Abstract

It is already well-understood that many delay differential equations with only a single constant delay exhibit a change in stability according to the value of the delay in relation to a critical delay value. Finding a formula for the critical delay is important to understanding the dynamics of delayed systems and is often simple to obtain when the system only has a single constant delay. However, if we consider a system with multiple constant delays, there is no known way to obtain such a formula that determines for what values of the delays a change in stability occurs. In this paper, we present some single-delay approximations to a multi-delay system obtained via a Taylor expansion as well as formulas for their critical delays which are used to approximate where the change in stability occurs in the multi-delay system. We determine when our approximations perform well and we give extra analytical and numerical attention to the two-delay and three-delay settings.

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Philip Doldo, Jamol Pender. 2020-12-09. Multi-Delay Differential Equations: A Taylor Expansion Approach. https://arxiv.org/abs/2012.05005

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