  The theory of electron-phonon interaction in the presence of strong
correlation has been investigated in the present work. Due to the so called
spin-charge separation, it is argued that the electron-phonon interaction in
the strongly interacting systems is fundamentally different from the weakly
interacting counterparts. Both spinons and holons are shown to carry electric
charge and couple to the electromagnetic field and consequently to phonons. A
systematic approach to calculate the dynamical charge of spinons and holons is
presented, followed by a discussion of implications of this model for the high
temperature superconductors. It is demonstrated that the unusual oxygen isotope
effect in high Tc materials can be easily understood within this framework.
