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Wick's theorem for q-deformed boson operators

Toufik Mansour·Matthias Schork·Simone Severini
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Abstract

In this paper combinatorial aspects of normal ordering arbitrary words in the creation and annihilation operators of the q-deformed boson are discussed. In particular, it is shown how by introducing appropriate q-weights for the associated ``Feynman diagrams'' the normally ordered form of a general expression in the creation and annihilation operators can be written as a sum over all q-weighted Feynman diagrams, representing Wick's theorem in the present context.

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Toufik Mansour, Matthias Schork, Simone Severini. 2007-03-11. Wick's theorem for q-deformed boson operators. https://doi.org/10.1088/1751-8113/40/29/014

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