Moduli of (1,7)-polarized Abelian surfaces via syzygies

Citation
N. Manolache et Fo. Schreyer, Moduli of (1,7)-polarized Abelian surfaces via syzygies, MATH NACHR, 226, 2001, pp. 177-203
Citations number
30
Categorie Soggetti
Mathematics
Journal title
MATHEMATISCHE NACHRICHTEN
ISSN journal
0025584X → ACNP
Volume
226
Year of publication
2001
Pages
177 - 203
Database
ISI
SICI code
0025-584X(2001)226:<177:MO(ASV>2.0.ZU;2-7
Abstract
We prove that the moduli space X(1,7) of (1,7)-polarized abelian surfaces w ith canonical level-structure is birational to the Fano 3-fold V-22 of pola r hexagons of the Klein quartic X(7). In particular X(1, 7) is rational and the birational map to P-3 is defined over Q. As a byproduct we obtain expl icitely the equations of the (1, 7)-very-ample-polarized abelian surfaces e mbedded in P-6.