Lower bounds on the modified K-energy and complex deformations

Andrew Clarke; Carl Tipler

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arXiv · 1302.0556

Lower bounds on the modified K-energy and complex deformations

Andrew Clarke·Carl Tipler

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Abstract

Let (X,L) be a polarized K\"ahler manifold that admits an extremal K\"ahler metric in c1(L). We show that on a nearby polarized deformation that preserves the symmetry induced by the extremal vector field of (X,L), the modified K-energy is bounded from below. This generalizes a result of Chen, Sz\'ekelyhidi and Tosatti to extremal metrics. Our proof also extends a convexity inequality on the space of K\"ahler potentials due to X.X. Chen to the extremal metric setup. As an application, we compute explicit polarized 4-points blow-ups of CP1\times CP1 that carry no extremal metric but with modified K-energy bounded from below.

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BibTeX RIS

Andrew Clarke, Carl Tipler. 2013-02-04. Lower bounds on the modified K-energy and complex deformations. https://arxiv.org/abs/1302.0556

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