QCD Ghost Dark Energy in RS II Braneworld with Bulk-Brane Interaction

We investigate the QCD ghost model of dark energy in the framework of RS II braneworld. We assume there is an energy flow between the brane and bulk, and hence the continuity equation for the ghost dark energy is violated, while it is still preserved for the dark matter on the brane. We find that with the brane-bulk interaction, the equation of state parameter of ghost dark energy on the brane, can cross the phantom line wD=−1 at the present time, which confirms by some cosmological evidences. This result is in contrast to the standard cosmology where wD of ghost dark energy never cross the phantom line and the universe enters a de Sitter phase at the late time.