Let HH be a complex , let S(H)S(H) be its , and let C(z)C(z) and C(z)C^*(z) be the associated with zHz\in H. The Fock–Cook field operator is the closure

R(z)=12(C(z)+C(z)),R(z)=\frac1{\sqrt2}\,(C(z)+C^*(z))^{\sim},

initially defined on the finite-particle subspace. The corresponding Weyl operators are

V(z)=eiR(z).V(z)=e^{iR(z)}.
Remarks

The unitaries V(z)V(z) satisfy the . In the setting of Shale's theorem, a symplectic transformation TSp(K)T\in Sp(K) is unitarily implementable in this representation exactly when TrSp(K)T\in rSp(K).

Examples
  • For finite-dimensional HH, this is the standard bosonic Fock representation of the canonical commutation relations.