  This thesis looks at the electronic energy transfer in the
Fenna-Matthews-Olson complex, in which evidence of long-lived coherence has
been observed in 2-dimensional infrared experiments. I use three techniques:
the numerically exact Hierarchical Equations of Motion, and the perturbative
Redfield and Foerster theories, the latter of which ignores quantum coherence
in the transfer. Both of the approximate methods perform very well - and while
oscillations in site populations (a hallmark of coherence) are present in the
exact transfer dynamics and absent in the dynamics of Foerster theory, the
latter gives a reasonable prediction of transfer rates and steady-state
populations, despite being incoherent - suggesting that coherence is not vital
for the dynamics of transfer. Since Foerster theory is very inexpensive to run
and performs so well, I then apply it to calculate the effects of static
disorder in bacteriochlorophyll site energies and of a more structured spectral
density. Ultimately, the energy transfer in the complex is found to be very
robust to changes in its environment, which is advantageous for its biological
function.
