Poincaré recurrence theorem
庞加莱回复定理
Meaning in context
For a probability-preserving transformation and measurable , almost every returns to infinitely often under positive iterates.
保概率系统中,可测集合内几乎所有点在正向迭代下无穷多次返回该集合的定理。
Example
A rotation preserving circle length has almost-everywhere returns to any measurable arc.
Usage and distinctions
Finite total measure is essential for this conclusion; translation on the integers with counting measure can have no returns.
Read the encyclopedia explanation
Recommended reading in this subject · Preparation & skip guidance
Definition sources
- Omri Sarig — Lecture Notes on Ergodic Theory§1.2, Theorem 1.1 (Poincaré's Recurrence Theorem) · Checked 2026-10-14
Translation sources
- 何伟鲲 — 遍历论课程大纲(中国科学院大学)大纲内容,第一章,第2节 回复性、庞加莱回复定理 · Checked 2026-10-14