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Equivalence Problem for Second Order Partially Differential Equations and Double Fibration as a Flat Model Space

Takahiro Noda
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Abstract

In this paper, we consider an equivalence problem of second order partially differential equations (PDE) and a duality of the flat differential equation. For the equivalence problem, explicit form of invariants (curvatures) are given. We also investigate a duality associated with the flat equation using double fibrations. These double fibrations are described in terms of transformation groups.

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Takahiro Noda. 2007-03-26. Equivalence Problem for Second Order Partially Differential Equations and Double Fibration as a Flat Model Space. https://arxiv.org/abs/math/0703747

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