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arXiv · 2509.17546

CM-line bundles and slope $\K$-semistability for big and nef line bundles along subschemes

Nathan Grieve
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Abstract

We apply the theory of the Chow-Mumford line bundle as developed by Arezzo-et-al and build on earlier key insights of Paul and Tian (see \cite{Arezzo:DellaVedova:LaNave} and the references therein). In particular, we give an explicit intersection theoretic description of the Donaldson-Futaki $\K$-stability invariants that arise via deformation to the normal cones along subschemes and with respect to big and nef line bundles on projective varieties. In doing so we generalize to the case of big and nef line bundles the slope stability theory of Ross and Thomas \cite[Section 4]{Ross:Thomas:2006}. A key point to what we do here is the continuity property of the Chow Mumford line bundles with respect to the ample cones of projective varieties.

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Nathan Grieve. 2026-09-11. CM-line bundles and slope $\K$-semistability for big and nef line bundles along subschemes. https://arxiv.org/abs/2509.17546

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