2408.15054
Torus and hyperchaos in 3D Lotka-Volterra map
Sishu Shankar Muni
uncertainmedium confidence
- Category
- Not specified
- Journal tier
- Specialist/Solid
- Processed
- Sep 28, 2025, 12:56 AM
- arXiv Links
- Abstract ↗PDF ↗
Audit review
The paper documents the bifurcation sequence for the 3D Lotka–Volterra map chiefly via numerical continuation, Lyapunov spectra, and eigenvalue plots, e.g., reporting a supercritical Neimark–Sacker at R ≈ 0.887, a saddle–node of invariant circles near R ≈ 0.943, a subcritical NS of a 2-cycle at R ≈ 1.1104, a saddle–node producing a 6-cycle near R ≈ 1.1112, and a final 6-cycle collision at R ≈ 1.1784, all for α = −0.227, β = −0.228, but without rigorous proofs or validated numerics for these global steps . The candidate solution gives a rigorous, fully worked local analysis for step (1) (NS of the fixed point), including an exact crossing parameter and sign of the first Lyapunov coefficient, but also explains why steps (2)–(5) remain nontrivial and likely open (at least not yet published rigorously) as of the cutoff. Therefore, the underlying problem is likely open as of the cutoff, with only step (1) settled rigorously by the model, while the paper remains numerical/empirical on the global claims.
Referee report (LaTeX)
\textbf{Recommendation:} major revisions \textbf{Journal Tier:} specialist/solid \textbf{Justification:} Compelling numerical evidence is presented for a rich bifurcation structure in the 3D Lotka–Volterra map, including torus phenomena, transitions to hyperchaos, and a rare period-2 to period-6 route. However, the central claims regarding specific global bifurcation mechanisms are supported only empirically. The work would benefit substantially from validated numerics or rigorous a posteriori arguments that certify the existence and nature of the reported invariant objects and bifurcations. Clarity would also improve by distinguishing conjectural from proved statements and by providing computational details sufficient for replication.