Document Type: Research Paper

**Authors**

Department of pure mathematics, Ferdowsi university of Mashhad, Mashhad, Iran.

**Abstract**

In this paper, we introduce chaotic measure for discrete and continuous dynamical systems and study some properties of measure chaotic systems. Also relationship between chaotic measure, ergodic and expansive measures is investigated. Finally, we prove a new version of variational principle for chaotic measure.

**Keywords**

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