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On the equations for universal torsors over del Pezzo surfaces

Published online by Cambridge University Press:  11 August 2009

Vera V. Serganova
Affiliation:
Department of Mathematics, University of California, Berkeley, CA 94720-3840, USA (serganov@math.berkeley.edu)
Alexei. N. Skorobogatov
Affiliation:
Department of Mathematics, South Kensington Campus, Imperial College London, London SW7 2BZ, UK (a.skorobogatov@imperial.ac.uk) and Institute for Information Transmission Problems, Russian Academy of Sciences, 19 Bolshoi Karetnyi, Moscow 127994, Russia

Abstract

We describe equations of the universal torsors over del Pezzo surfaces of degrees from 2 to 5 over an algebraically closed field in terms of the equations of the corresponding homogeneous space G/P. We also give a generalization for fields that are not algebraically closed.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2010

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