The 2×2-matrix structure of Green's functions is a common feature for the real-time formalisms of quantum field theory under thermal situations, such as the closed time path formalism and Thermo Field Dynamics (TFD). It has been believed to originate from quantum nature. Recently, Galley has proposed the Hamilton's principle with initial data for nonconservative classical systems, doubling each degree of freedom . We show that the Galley's Hamilton formalism can be extended to quantum field and that the resulting theory is naturally identical with nonequilibrium TFD.
|ジャーナル||Physics Letters, Section A: General, Atomic and Solid State Physics|
|出版物ステータス||Published - 2013 12 9|
ASJC Scopus subject areas
- Physics and Astronomy(all)