Staggered fermion

Staggered fermion is a technical subtlety that arises when fermionic fields are included in lattice gauge theory. When one does so, many new unphysical fermionic excitations corresponding to alternating fermionic fields occur in the spectrum. This is known as the fermion doubling problem. A particular way to resolve this problem, first proposed by Leonard Susskind and John Kogut ( Kogut-Susskind fermion), is the staggered fermion approach where a new nonlocal action is constructed where the Dirac operator is treated as a square root.