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arXiv · hep-ph/9907490

Time Ordering, Energy Ordering, and Factorization

C. S. Lam
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Abstract

Relations between integrals of time-ordered product of operators, and their representation in terms of energy-ordered products are studied. Both can be decomposed into irreducible factors and these relations are discussed as well. The energy-ordered representation was invented to separate various infrared contributions in gauge theories. It is shown that the irreducible time-ordered expressions can be used to accomplish the same purpose. Besides, it has the added advantage of being factorizable.

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C. S. Lam. 1999-07-26. Time Ordering, Energy Ordering, and Factorization. https://doi.org/10.1063/1.533356

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