  We calculate the dynamical structure factor of the \nu=5/2 non-abelian
quantum Hall state in the dipole approximation, valid for large momenta. Due to
the fact that both quasi-particles (qps) and quasi-holes (qhs) have an internal
Majorana degree of freedom, a qp-qh pair has a fermionic degree of freedom
which can be either empty or occupied, and leads to a splitting of the roton
mode. Observation of this splitting by means of finite wavelength optical
spectroscopy could provide evidence for Majorana modes in the \nu=5/2 quantum
Hall state.
