We drive the cosmological solutions of five-dimensional model with 1/H2
term (H2≡HMNPQHMNPQ), where HMNPQ is 4-form field
strength. The behaviors of the scale factors and the scalar potential in
effective theory are examined.As a consequence, we show that the universe
changes from decelerated expansion to accelerated expansion in Einstein frame
of the four-dimensional theory.Comment: 10 pages, 2 figures, version to appear in JCA