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Combinatorial invariant for Morse-Smale diffeomorphisms on surfaces with orientable heteroclinic
D Malyshev1, A Morozov1, O Pochinka1
1Faculty of Informatics, Mathematics, and Computer Science, National Research University Higher School of Economics, Nizhny Novgorod 603155, Russian Federation.
This study introduces a new graph-based method for classifying Morse-Smale diffeomorphisms on surfaces. This approach enables an effective algorithm for distinguishing graph isomorphisms, aiding in classification problems.
Area of Science:
- Dynamical Systems and Differential Geometry
- Topology
Background:
- Morse-Smale diffeomorphisms on orientable surfaces possess a finite number of heteroclinic orbits.
- Classification of these diffeomorphisms is linked to distinguishing orientable graphs, a problem lacking efficient algorithms.
Purpose of the Study:
- To develop a novel, effective algorithm for classifying orientation-preserving Morse-Smale diffeomorphisms.
- To address the challenge of distinguishing complex orientable graphs associated with these dynamical systems.
Main Methods:
- Associating each diffeomorphism with a specific graph structure.
- Developing an effective algorithm for graph isomorphism testing based on these associated graphs.
- Identifying a class of admissible graphs realizable by surface diffeomorphisms.
Main Results:
- A new approach to classifying Morse-Smale diffeomorphisms is proposed.
- An effective algorithm for determining graph isomorphism is constructed.
- A class of admissible graphs is identified, linked to surface diffeomorphisms with orientable heteroclinics.
Conclusions:
- The findings provide a method for constructing representatives in homotopy classes of homeomorphisms.
- This work offers an approach to solving the open problem of realizing Nielsen's algebraically finite type homeomorphisms.
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