Stability and periodicity in dynamic delay equations

Abstract

Let T be an arbitrary time scale that is unbounded above. By means of a variation of Lyapunov's method and contraction mapping principle this paper handles asymptotic stability of the zero solution of the completely delayed dynamic equations x(Delta)(t) = -a(t)x(delta(t))delta(Delta)d(t). Moreover, if T is a periodic time scale, then necessary conditions are given for the existence of a unique periodic solution of the above mentioned equation. (c) 2009 Elsevier Ltd. All rights reserved.