Lie triple derivations on nest algebras

Let delta be a Lie triple derivation from a nest algebra A into an A-bimodule M. We show that if M is a weak* closed operator algebra containing A then there are an element S is an element of M and a linear functional f on A such that delta(A) = SA - AS + f (A)I for all A is an element of A, and if M is the ideal of all compact operators then there is a compact operator K such that delta(A) = KA - AK for all A is an element of A. As applications, Lie derivations and Jordan derivations on nest algebras are characterized. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.