Simple example of local temperature stateAiming at a general formulation of non-equilibrium states in the framework of QFT, we start from a simple model-example of local temperature state: Let
φ(x) be a massless free scalar field (in four dimensions) characterized by(Given a two-point function
ω(2)(φ(x)φ(y)) , we can define a quasi-free state
ω of
φ through the Wick formula:When a two-point function
ω(2) is chosen consistently with Eqs.
(1,2) asthe corresponding quasi-free state
ω=ωβ describes a global thermal equi- librium satisfying the KMS condition for any pair of polynomial fields
A= φ(x1)⋯φ(xr) and
B=φ(y1)⋯φ(ys) ,
ωβ(Aα(iβ,O)(B))=ωβ(BA) , (5) *Talk based on a joint work of D.Buchholz, H.Roos and
I.O . in progress