A system equivalence related to Dulac’s extension of Bendixson’s negative theorem for planar dynamical systems

Autor: Charlie H. Cooke
Jazyk: angličtina
Předmět:
Zdroj: Applied Mathematics Letters. (11):1291-1292
ISSN: 0893-9659
DOI: 10.1016/j.aml.2006.04.003
Popis: Bendixson’s Theorem [H. Ricardo, A Modern Introduction to Differential Equations, Houghton-Mifflin, New York, Boston, 2003] is useful in proving the non-existence of periodic orbits for planar systems (1) d x d t = F ( x , y ) , d y d t = G ( x , y ) in a simply connected domain D , where F , G are continuously differentiable. From the work of Dulac [M. Kot, Elements of Mathematical Ecology, 2nd printing, University Press, Cambridge, 2003] one suspects that system (1) has periodic solutions if and only if the more general system (2) d x d τ = B ( x , y ) F ( x , y ) , d y d τ = B ( x , y ) G ( x , y ) does, which makes the subcase (1) more tractable, when suitable non-zero B ( x , y ) which are C 1 ( D ) can be found. Thus, Bendixson’s Theorem can be applied to system (2) , where otherwise it is unfruitful in establishing the non-existence of periodic solutions for system (1) . The object of this note is to give a simple proof justifying this Dulac-related postulate of the equivalence of systems (1) , (2) .
Databáze: OpenAIRE