The lecture, entitled Faith, Reason and the University: Memories and Reflections, explored the historical and philosophical differences between Islam and Christianity, and the relationship between violence and faith.

BBC: Pope Benedict XVI in his own words

The high-frequency sound from the transmitter produces sharp reflections of small objects for the same reason that an electron microscope (which operates at high frequencies) can see smaller things than a light microscope (which operates at low frequencies).

ECONOMIST: Archaeology