Abstract
We present new exact solutions of the low-energy-effective-action string equations with both dilaton $\ensuremath{\varphi}$ and axion $H$ fields nonzero. The background universe is Kantowski-Sachs-type. We consider the possibility of a pseudoscalar axion field $h$ [${H=e}^{\ensuremath{\varphi}}{(\mathrm{dh})}^{*}$] that can be either time or space dependent. The case of a time-dependent $h$ reduces to that of a stiff perfect-fluid cosmology. For a space-dependent $h$ there is just one nonzero time-space-space component of the axion field $H$, and this corresponds to a distinguished direction in space which prevents the models from isotropizing. Also, in the latter case, both the axion field $H$ and its tensor potential $B$ $(H=dB)$ are dependent on time and space, yet the energy-momentum tensor remains time dependent as required by the homogeneity of the cosmological model.
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