Particle production in higher derivative theory

The effect of particle production on the evolution of the spatially flat Fr iedmann-Lemaitre-Robertson-Walker cosmological model during the early stage s of the universe is analysed in the framework of higher derivative theory. The universe has been considered as an open thermodynamic system where par ticle production gives rise to a supplementary negative creation pressure i n addition to the thermodynamic pressure. The dynamical behaviour of both e xponential as well as power law solutions have been discussed.