ar X iv : m at h / 06 02 64 2 v 1 [ m at h . A G ] 2 8 Fe b 20 06 DIVISOR CLASSES AND THE VIRTUAL CANONICAL BUNDLE FOR GENUS 0 MAPS
نویسنده
چکیده
Some divisor class relations for genus 0 curves are proved and used to compute the Cartier divisor class of the virtual canonical bundle for genus 0 maps to a smooth target. Many results here first appeared in [6] and [5]; our proofs use a completely different method.
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