Bad reduction of genus 2 curves with CM jacobian varieties

Habegger, Philipp and Pazuki, Fabien. (2015) Bad reduction of genus 2 curves with CM jacobian varieties. Preprints Fachbereich Mathematik, 2015 (25).

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We show that a genus 2 curve over a number field whose jacobian has complex multiplication will usually have stable bad reduction at some prime. We prove this by computing the Faltings height of the jacobian in two different ways. First, we use a formula by Colmez and Obus specific to the CM case and valid when the CM field is an abelian extension of the rationals. This formula links the height and the logarithmic derivatives of an L-function. The second formula involves a decomposition of the height into local terms based on a hyperelliptic model. We use the reduction theory of genus 2 curves as developed by Igusa, Liu, Saito, and Ueno to relate the contribution at the finite places with the stable bad reduction of the curve. The subconvexity bounds by Michel and Venkatesh together with an equidistribution result of Zhang are used to bound the infinite places.
Faculties and Departments:05 Faculty of Science > Departement Mathematik und Informatik > Mathematik > Zahlentheorie (Habegger)
12 Special Collections > Preprints Fachbereich Mathematik
UniBasel Contributors:Habegger, Philipp
Item Type:Preprint
Publisher:Universität Basel
edoc DOI:
Last Modified:08 May 2019 18:43
Deposited On:28 Mar 2019 09:51

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