  It is a well known result that the scalar field is composed of two chiral
particles (Floreanini-Jackiw particles) of opposite chiralities. Also, that a
Siegel particle spectrum is formed by a nonmover field (a Hull's noton) and a
FJ particle. In this work we show that in a scalar field spectrum, in a curved
expanding universe scenario, we can find two dynamical chiral fields.
