Uploaded July 2026 | Updated September 2026, 3 weeks ago
This lecture develops the path-integral description of open quantum systems using the closed
time contour. Topics include: - The Schwinger–Keldysh (in-in) formalism, - Doubling of fields and the structure of the closed time path, - In-in Feynman rules and perturbation theory for open systems, retarded, advanced and Keldysh propagators, - Noise, dissipation, and influence functionals, - Constraints from ultraviolet unitarity, locality, and symmetries. The equivalence between operator and path-integral approaches is emphasized, together with
the structural constraints imposed by unitarity and symmetries at high energies.
Enrico Pajer (DAMTP, University of Cambridge)
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Find this and many more scientific videos on carmin.tv - a French video platform for mathematics and their interactions with other sciences offering extra functionalities tailored to meet the needs of the research community.
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This lecture develops the path-integral description of open quantum systems using the closed
time contour. Topics include: - The Schwinger–Keldysh (in-in) formalism, - Doubling of fields and the structure of the closed time path, - In-in Feynman rules and perturbation theory for open systems, retarded, advanced and Keldysh propagators, - Noise, dissipation, and influence functionals, - Constraints from ultraviolet unitarity, locality, and symmetries. The equivalence between operator and path-integral approaches is emphasized, together with
the structural constraints imposed by unitarity and symmetries at high energies.
Enrico Pajer (DAMTP, University of Cambridge)
===
Find this and many more scientific videos on carmin.tv - a French video platform for mathematics and their interactions with other sciences offering extra functionalities tailored to meet the needs of the research community.
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