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arXiv · hep-th/0307118

Central extensions, classical non-equivariant maps and residual symmetries

Francesco Toppan
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Abstract

The arising of central extensions is discussed in two contexts. At first classical counterparts of quantum anomalies (deserving being named as "classical anomalies") are associated with a peculiar subclass of the non-equivariant maps. Further, the notion of "residual symmetry" for theories formulated in given non-vanishing EM backgrounds is introduced. It is pointed out that this is a Lie-algebraic, model-independent, concept.

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Francesco Toppan. 2003-07-13. Central extensions, classical non-equivariant maps and residual symmetries. https://doi.org/10.1016/s0920-5632(03)02432-0

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