  We theoretically investigate light matter interactions for chiral molecules
in the presence of non-chiral nanoantennas. Isotropic nanostructures supporting
optical-frequency electric or magnetic dipoles are sufficient to locally
enhance the excitation of a molecule's chiral polarizability and thus its
circular dichroism spectrum. However, simultaneous electric and magnetic
dipoles are necessary to achieve a net, spatially-averaged enhancement. Our
contribution provides a theoretical framework to understand chiral light-matter
interactions at the nanoscale and sets the necessary and sufficient conditions
to enhance circular dichroism spectroscopy in the presence of nanoantennas. The
results may lead to new, field-enhanced, chiral spectroscopic techniques.
