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arXiv · hep-th/9710225

Causal Perturbation Theory and Differential Renormalization

Dirk Prange
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Abstract

In Causal Perturbation Theory the process of renormalization is precisely equivalent to the extension of time ordered distributions to coincident points. This is achieved by a modified Taylor subtraction on the corresponding test functions. I show that the pullback of this operation to the distributions yields expressions known from Differential Renormalization. The subtraction is equivalent to BPHZ subtraction in momentum space. Some examples from Euclidean scalar field theory in flat and curved spacetime will be presented.

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Dirk Prange. 1997-10-29. Causal Perturbation Theory and Differential Renormalization. https://doi.org/10.1088/0305-4470%2F32%2F11%2F015

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