3 papers
math.DS2026
Discrete averaging for discrete time dynamical systems
Vassili Gelfreich, Arturo Vieiro
In this paper we develop the theory of discrete averaging designed to study discrete time dynamical systems defined by iterates of a map. The discrete averaging uses weighted avera…
math.DS2024
On exponentially accurate approximation of a near the identity map by an autonomous flow
V. Gelfreich, A. Vieiro
This paper contains a proof of a refined version of Neishtadt's theorem which states that an analytic near-identity map can be approximated by the time-one map of an autonomous flo…
math.DS2024
Nekhoroshev theory and discrete averaging
V. Gelfreich, A. Vieiro
This paper contains a proof of the Nekhoroshev theorem for quasi-integrable symplectic maps. In contrast to the classical methods, our proof is based on the discrete averaging meth…