Sir Alfred Brian Pippard, ScD, FRS, was a British physicist. He was Cavendish Professor of Physics from 1971 until 1984 and an Honorary Fellow of Clare Hall, Cambridge, of which he was the first President. He was educated at Clifton College.
Pippard demonstrated the reality, as opposed to the mere abstract concept, of Fermi surfaces in metals by establishing the shape of the Fermi surface of copper through measuring the reflection and absorption of microwave electromagnetic radiation. He also introduced the notion of coherence length in superconductors in his proposal for the non-local generalisation of the Londons' equations concerning electrodynamics in superfluids and superconductors. The non-local kernel proposed by Pippard, inferred on the basis of Chambers' non-local generalisation of Ohm's law can be deduced within the framework of the BCS theory of superconductivity.
Pippard was the author of Elements of Classical Thermodynamics for Advanced Students of Physics, Dynamics of Conduction Electrons, and The Physics of Vibration. He is also a co-author of the three-volumes encyclopaedia Twentieth Century Physics. As the Cavendish Professor of Physics at Cavendish Laboratory, University of Cambridge, he complied Cavendish Problems in Classical Physics, based in large part on past examination questions for Cambridge physics students.