Group Actions, Divisors, and Plane Curves

Araceli Bonifant; John Milnor

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arXiv · 1809.05191

Group Actions, Divisors, and Plane Curves

Araceli Bonifant·John Milnor

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Abstract

After a general discussion of group actions, orbifolds, and "weak orbifolds" this note will provide elementary introductions to two basic moduli spaces over the real or complex numbers: First the moduli space of effective divisors with finite stabilizer on the projective space ${\mathbb P}^1$ modulo the group ${\rm PGL}_2$ of projective transformations of ${\mathbb P}^1$; and then the moduli space of effective 1-cycles with finite stabilizer on ${\mathbb P}^2$ modulo the group ${\rm PGL}_3$ of projective transformations of ${\mathbb P}^2$.

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Araceli Bonifant, John Milnor. 2018-09-13. Group Actions, Divisors, and Plane Curves. https://arxiv.org/abs/1809.05191

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