On degenerations and extensions of symplectic and orthogonal quiver representations

We discuss degenerations of symplectic and orthogonal representations of symmetric quivers and algebras with self-dualities. As in the nonsymmetric case, we define a partial ordering, that we call symmetric Ext-order which gives a sufficient criterion for a symmetric degeneration. Then a detailed discussion of type A quivers and their (symmetric) representation theory via Auslander-Reiten theory leads to our main theorem which states that the symmetric degeneration order of a symmetric quiver of finite type is induced by the ”usual” degeneration order between representations of the underlying quiver.

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