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arXiv · 1507.02643

Spin canonical rings of log stacky curves

Aaron Landesman·Peter Ruhm·Robin Zhang
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Abstract

Consider modular forms arising from a finite-area quotient of the upper-half plane by a Fuchsian group. By the classical results of Kodaira-Spencer, this ring of modular forms may be viewed as the log spin canonical ring of a stacky curve. In this paper, we tightly bound the degrees of minimal generators and relations of log spin canonical rings. As a consequence, we obtain a tight bound on the degrees of minimal generators and relations for rings of modular forms of arbitrary integral weight.

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Aaron Landesman, Peter Ruhm, Robin Zhang. 2016-03-07. Spin canonical rings of log stacky curves. https://doi.org/10.5802/aif.3065

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