Dynamics of inflation with mutually orthogonal vector fields in a closed
  universe
  We study the dynamics of a homogeneous, isotropic, and positively curved
universe in the presence of a SU(2) gauge field or a triplet of mutually
orthogonal vector fields. In the SU(2) case we use the previously known ansatz
for the gauge-field configuration, but the case without non-abelian symmetries
is more nontrivial and we develop a new ansatz. We in particular consider
axion-SU(2) inflation and inflation with vector fields having
U(1)$\times$U(1)$\times$U(1) symmetry, and analyze their dynamics in detail
numerically. Novel effects of the spatial curvature come into play through
vector fields, which causes unconventional pre-inflationary dynamics. It is
found that the closed universe with vector fields is slightly more stable
against collapse than that filled solely with an inflaton field.
