From sine waves to square waves in delay equations

Abstract

SynopsisSuppose fλ: ℝ→ℝ, fλ(0) = 0 and the fixed point zero undergoes a generic supercritical period doubling bifurcation at λ = 0. We characterise those small values of ε > 0, λ ∈ ℝ for which there are periodic solutions of period approximately two of the equationAs ε → 0, these solutions approach square waves.