Holography for fermions

The holographic interpretation is a useful tool to describe 5D field theories in a 4D language. In particular it allows one to relate 5D AdS theories with 4D CFTs. We elaborate on the 5D/4D dictionary for the case of fermions in AdS${}_5$ with boundaries. This dictionary is quite useful to address phenomenological issues in a very simple manner, as we show by giving some examples.