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arXiv · 2406.02489

Stability theory over toroidal or Novikov type base and Canonical modifications

Yuji Odaka
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Abstract

We set up a generalization of ubiquitous one-parameter families in algebraic geometry and their use for stability theories ([GIT, HL, AHLH]) to families over toric varieties and their analytic analogues. The language allows us to reformulate degenerations of ``irrational" direction in the literature as canonical objects in a unified manner. Accordingly, we generalize the (semi)stable reduction-type theorem for $\Theta$-stratification in [AHLH] of Langton type to our higher rank setup. We also establish a complex analytic analogue of the results. As an infinitesimal analogue of toric spectrum, we also use Novikov type rings, as they provide greater canonicity, but their use can be avoided logically for readers who prefer not to use such rings. Our other papers discuss applications of our framework and the main theorems to problems around K-stability and Kahler geometry.

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Yuji Odaka. 2024-06-04. Stability theory over toroidal or Novikov type base and Canonical modifications. https://arxiv.org/abs/2406.02489

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