  We study optical excitations across the Mott gap in the multi-orbital
Mott-Hubbard insulators RVO3. The multi-peak structure observed in the optical
conductivity can be described consistently in terms of the different 3d^3
multiplets or upper Hubbard bands. The spectral weight is very sensitive to
nearest-neighbor spin-spin and orbital-orbital correlations and thus shows a
pronounced dependence on both temperature and polarization. Comparison with
theoretical predictions based on either rigid orbital order or strong orbital
fluctuations clearly rules out the latter. Both, the line shape and the
temperature dependence give clear evidence for the importance of excitonic
effects.
