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Second flip in the Hassett–Keel program: existence of good moduli spaces

Published online by Cambridge University Press:  15 May 2017

Jarod Alper
Affiliation:
Mathematical Sciences Institute, Australian National University, Canberra, ACT 0200, Australia email [email protected]
Maksym Fedorchuk
Affiliation:
Mathematics Department, Boston College, 140 Commonwealth Ave, Chestnut Hill, MA 02467, USA email [email protected]
David Ishii Smyth
Affiliation:
Mathematical Sciences Institute, Australian National University, Canberra, ACT 0200, Australia email [email protected]

Abstract

We prove a general criterion for an algebraic stack to admit a good moduli space. This result may be considered as a generalization of the Keel–Mori theorem, which guarantees the existence of a coarse moduli space for a separated Deligne–Mumford stack. We apply this result to prove that the moduli stacks $\overline{{\mathcal{M}}}_{g,n}(\unicode[STIX]{x1D6FC})$ parameterizing $\unicode[STIX]{x1D6FC}$-stable curves introduced in [J. Alper et al., Second flip in the Hassett–Keel program: a local description, Compositio Math. 153 (2017), 1547–1583] admit good moduli spaces.

Type
Research Article
Copyright
© The Authors 2017 

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