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arXiv · 2507.01232

Torus actions, weighted blow-ups, and desingularization of plane curves

Dan Abramovich·Ming Hao Quek·Bernd Schober
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Abstract

Given a singular hypersurface in a regular 2-dimensional scheme essentially of finite type over a field, we construct an embedded resolution of singularities by weighted blow-ups. This differs from our earlier work which required multi-weighted blow-ups. We deduce an inductive argument, despite the fact that higher dimensional tangent spaces arise, by taking torus actions and equivariant centers into account. In addition, we do not have to restrict to perfect base fields.

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Dan Abramovich, Ming Hao Quek, Bernd Schober. 2025-07-01. Torus actions, weighted blow-ups, and desingularization of plane curves. https://arxiv.org/abs/2507.01232

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