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arXiv · 1904.04050

Inclusive scattering matrix and scattering of quasiparticles

Albert Schwarz
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Abstract

The quantum theory can be formulated in the language of positive functionals on Weyl or Clifford algebra ($L$-functionals). It is shown that this language gives simple understanding of diagrams of Keldysh formalism (that coincide in our case with the diagrams of thermo-field dynamics). The matrix elements of the scattering matrix in the formalism of $L$-functionals are related to inclusive cross-sections, therefore we suggest the name "inclusive scattering matrix" for this notion. The inclusive scattering matrix can be expressed in terms of on-shell values of generalized Green functions. This notion is necessary if we want to analyze collisions of quasiparticles.

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Albert Schwarz. 2019-04-08. Inclusive scattering matrix and scattering of quasiparticles. https://doi.org/10.1016/j.nuclphysb.2019.114869

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