ArticleOriginal scientific text
Title
The Abel equation and total solvability of linear functional equations
Authors 1, 2
Affiliations
- Ben-Gurion University of the Negev, 84105 Beer-Sheva, Israel
- Department of Mathematics, Technion, 32000 Haifa, Israel
Abstract
We investigate the solvability in continuous functions of the Abel equation φ(Fx) - φ(x) = 1 where F is a given continuous mapping of a topological space X. This property depends on the dynamics generated by F. The solvability of all linear equations P(x)ψ(Fx) + Q(x)ψ(x) = γ(x) follows from solvability of the Abel equation in case F is a homeomorphism. If F is noninvertible but X is locally compact then such a total solvability is determined by the same property of the cohomological equation φ(Fx) - φ(x) = γ(x). The smooth situation can also be considered in this way.
Keywords
functional equation, Abel equation, cohomological equation, wandering set
Bibliography
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