• Corpus ID: 232148084

The structure group for quasi-linear equations via universal enveloping algebras

  title={The structure group for quasi-linear equations via universal enveloping algebras},
  author={Pablo Linares and Felix Otto and Markus Tempelmayr},
We consider the approach of replacing trees by (fewer) multi-indices as an index set of the abstract model space T, which was introduced in [15] to tackle quasi-linear singular SPDE. We show that this approach is consistent with the postulates of regularity structures in [10] when it comes to the structure group G. In particular, G ⊂ Aut(T) arises from a Hopf algebra T and a comodule ∆: T → T ⊗ T. In fact, this approach, where the dual T of the abstract model space T naturally embeds into a… 
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