2025/08/19 by Zhicheng Tong, Yong Li, Tong, Zhicheng +1
Engineering · Mathematics · Physics and Astronomy · #37K55 #37K60 #37L60 #Dynamical Systems (math.DS) #FOS: Mathematics #FOS: Physical sciences #Mathematical Physics (math-ph) #Quantum chaos and dynamical systems #Spectral Theory in Mathematical Physics #Stability and Controllability of Differential Equations
paper · pdf · doi:10.48550/arxiv.2508.13501
openalex publication_date 2025/08/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this paper, we present two infinite-dimensional Kolmogorov theorems based on non-resonant frequencies of Bourgain's Diophantine type or even weaker conditions. To be more precise, under a Legendre-type nondegeneracy condition for an infinite-dimensional Hamiltonian system, we prove the persistence of a full-dimensional KAM torus with a universally prescribed frequency independent of any spectral asymptotics. As an application, we prove that for a class of perturbed networks with weakly coupled oscillators described by \frac\rm d2xn\rm dt2 + V'( xn ) = εn W'( xn + 1 - xn ) - εn-1W'( xn - xn - 1 ) , n ∈ ℤ, or even for more general perturbed networks, frequency-preserving almost periodic breathers do persist, provided that the local potential V and the coupling potential W satisfy certain assumptions. In particular, this yields the first frequency-preserving result for the Aubry--MacKay conjecture [MA94,Aub95].