### Abstract

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 [1]. 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.

Original language | English |
---|---|

Pages (from-to) | 3102-3105 |

Number of pages | 4 |

Journal | Physics Letters, Section A: General, Atomic and Solid State Physics |

Volume | 377 |

Issue number | 43 |

DOIs | |

Publication status | Published - 2013 Dec 9 |

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### Keywords

- Canonical quantization
- Nonconservative system
- Nonequilibrium
- Quantum field theory
- Reservoir model
- Thermo Field Dynamics

### ASJC Scopus subject areas

- Physics and Astronomy(all)

### Cite this

**From classical mechanics with doubled degrees of freedom to quantum field theory for nonconservative systems.** / Kuwahara, Y.; Nakamura, Y.; Yamanaka, Yoshiya.

Research output: Contribution to journal › Article

*Physics Letters, Section A: General, Atomic and Solid State Physics*, vol. 377, no. 43, pp. 3102-3105. https://doi.org/10.1016/j.physleta.2013.10.001

}

TY - JOUR

T1 - From classical mechanics with doubled degrees of freedom to quantum field theory for nonconservative systems

AU - Kuwahara, Y.

AU - Nakamura, Y.

AU - Yamanaka, Yoshiya

PY - 2013/12/9

Y1 - 2013/12/9

N2 - 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 [1]. 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.

AB - 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 [1]. 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.

KW - Canonical quantization

KW - Nonconservative system

KW - Nonequilibrium

KW - Quantum field theory

KW - Reservoir model

KW - Thermo Field Dynamics

UR - http://www.scopus.com/inward/record.url?scp=84886722636&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84886722636&partnerID=8YFLogxK

U2 - 10.1016/j.physleta.2013.10.001

DO - 10.1016/j.physleta.2013.10.001

M3 - Article

AN - SCOPUS:84886722636

VL - 377

SP - 3102

EP - 3105

JO - Physics Letters, Section A: General, Atomic and Solid State Physics

JF - Physics Letters, Section A: General, Atomic and Solid State Physics

SN - 0375-9601

IS - 43

ER -