Dynamic equation on time scales

Summary

A dynamic equation on a time scale is an equation that involves the delta derivative of an unknown function. The function lives on a time scale $\mathbb{T}$, a nonempty closed subset of $\R$. It is the basic object of time-scale calculus. On $\mathbb{T} = \R$ it is an ordinary differential equation, and on $\mathbb{T} = \Z$ it is a recurrence relation, so one theory covers both cases at once.