Functional Invariants in Semilocal Bifurcations
In [7] an open set of structurally unstable families of vector fields on a sphere was constructed. More precisely, a vector field with a degeneracy of codimension three was discovered whose bifurcation in a generic three-parameter family has a numeric invariant. This vector field has a polycycle and two saddles, one inside and one outside this polycycle; one separatrix of the outside saddle winds towards the polycycle and one separatrix of the inside saddle winds from it. Families with functional invariants were constructed also. In [2] a hyperbolic polycycle with five vertices and no saddles outside it was constructed whose bifurcations in its arbitrary narrow neighborhood (semilocal bifurcations in other words) have a numeric invariant and thus are structurally unstable. This paper deals with semilocal bifurcations. A hyperbolic polycycle with nine edges is constructed whose semilocal bifurcation in an open set of nine-parameter families has a functional invariant.
Authors
- Yu. Ilyashenko (ORCID: https://orcid.org/0000-0003-1087-5903)
Institutions
- National Research University Higher School of Economics (RU)
- Independent University of Moscow (RU)
Publication Details
- Journal
- Regular and Chaotic Dynamics
- Published
- 2025-08-01
- DOI
- https://doi.org/10.1134/s1560354725040112
- Primary Topic
- Advanced Differential Equations and Dynamical Systems
- Type
- article
- Field-Weighted Citation Impact
- 0.00