activity
20242026
collaborators

9 papers

math.DS2026

Laskar's frequency map analysis revisited

Zhicheng Tong, Yong Li

In this paper, we establish the exponential convergence of Laskar's pioneering frequency map analysis, strictly improving upon classical polynomial bounds. By utilizing appropriate…

math.DS2026

Optimal rates of uniform convergence for weighted Birkhoff averages via almost all rotations

Zhicheng Tong, Yong Li

In this paper, we investigate weighted Birkhoff averages for toral translations associated with compactly supported weighting functions. By introducing several new analytical techn…

math.DS2026

Sharp regularity of a weighted Sobolev space over and its relation to finitely differentiable KAM theory

Zhicheng Tong, Yong Li

In this paper, we investigate the sharp regularity properties of a special weighted Sobolev space defined on the -dimensional torus, which is of independent interest. As a key…

math.DS2026

An infinite-dimensional Kolmogorov theorem and the construction of almost periodic breathers

Zhicheng Tong, Yong Li

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 precis…

math.DS2026

Weighted Birkhoff averages: Deterministic and probabilistic perspectives

Zhicheng Tong, Yong Li

In this paper, we survey physically related applications of a class of weighted quasi-Monte Carlo methods from a theoretical, deterministic perspective, and establish quantitative…

math.DS2025

Weighted multiple ergodic averages via analytic observables over : Is exponential pointwise convergence universal?

Zhicheng Tong, Yong Li

By employing an accelerated weighting method, we establish arbitrary polynomial and exponential pointwise convergence for multiple ergodic averages under general balancing conditio…