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arXiv · 0804.0414

Twisted cscK metrics and Kähler slope stability

Jacopo Stoppa
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Abstract

We introduce a cohomological obstruction to solving the constant scalar curvature Kähler (cscK) equation twisted by a semipositive form, appearing in works of Fine and Song-Tian. Geometrically this gives an obstruction for a manifold to be the base of a holomorphic submersion carrying a cscK metric in certain ``adiabatic'' classes. In turn this produces many new examples of general type threefolds with classes which do not admit a cscK representative. When the twist vanishes our obstruction extends the slope stability of Ross-Thomas to effective divisors on a Kähler manifold. Thus we find examples of non-projective slope unstable manifolds.

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Jacopo Stoppa. 2008-04-02. Twisted cscK metrics and Kähler slope stability. https://arxiv.org/abs/0804.0414

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