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Multifractal Analysis of Measures Arising from Random Substitutions
1School of Mathematics, University of Birmingham, Edgbaston, B15 2TT UK.
Summary
This study introduces random substitutions to analyze frequency measures, deriving analytic formulas for the spectrum and proving multifractal formalism. These findings offer new insights into complex systems and entropy calculations.
Area of Science:
- Dynamical Systems and Ergodic Theory
- Fractal Geometry
- Probability Theory
Background:
- Random substitutions generalize deterministic ones, creating complex frequency measures.
- Understanding regularity properties of these measures is crucial for analyzing complex systems.
- The multifractal formalism provides a framework for characterizing irregular measures.
Purpose of the Study:
- To investigate the regularity properties of frequency measures generated by random substitutions.
- To derive analytic formulas for the spectrum of these measures.
- To establish the validity of the multifractal formalism for a new class of measures.
Main Methods:
- Analysis of frequency measures arising from random substitutions.
- Derivation of closed-form analytic formulas for the spectrum.
- Introduction and analysis of the 'inflation word' spectrum.
- Application of separation conditions to recover known results.
Main Results:
- A closed-form analytic formula for the spectrum is derived for a natural class of random substitution measures.
- The multifractal formalism is proven to hold for these measures.
- Results concerning the spectrum are established for a broader class of frequency measures.
- The 'inflation word' spectrum is shown to coincide with the spectrum of the frequency measure.
Conclusions:
- This work introduces a novel class of measures satisfying the multifractal formalism.
- The findings provide a deeper understanding of regularity properties in random substitution systems.
- The derived formulas and methods have applications in calculating topological and measure theoretic entropy.
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