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Quaternionic Kähler and hyperKähler manifolds with torsion and twistor spaces

Stefan Ivanov·Ivan Minchev
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Abstract

The target space of a (4,0) supersymmetric two-dimensional sigma model with Wess-Zumino term has a connection with totally skew-symmetric torsion and holonomy contained in Sp(n)Sp(1) (resp. Sp(n)), QKT (resp. HKT)-spaces. We study the geometry of QKT, HKT manifold and their twistor spaces. We show that the Swann bundle of a QKT manifold admits a HKT structure with special symmetry if and only if the twistor space of the QKT manifold admits an almost hermitian structure with totally skew-symmetric Nijenhuis tensor, thus connecting two structures arising from quantum field theories and supersymmetric sigma models with Wess-Zumino term.

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Stefan Ivanov, Ivan Minchev. 2003-09-11. Quaternionic Kähler and hyperKähler manifolds with torsion and twistor spaces. https://arxiv.org/abs/math/0112157

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