The concept of frustration was introduced in physics by Gérard Toulouse and
Philip Anderson to designate the absence in certain magnetic systems (spin
glasses) of a global configuration of the spins allowing all pairs of
neighboring spins to achieve a local configuration of minimal energy. An
obvious example of magnetic frustration is provided by a triangular lattice of
spins in antiferromagnetic interaction (i.e., two neighboring spins prefer a
“head to tail” orientation.
