Marc Levine
Published 2017-03-08Version 1
We develop various aspects of classical enumerative geometry, including Euler characteristics and formulas for counting degenerate fibres in a pencil, with the classical numerical formulas being replaced by identitites in the Grothendieck-Witt group of quadratic forms with coefficients in the base-field.
Decompositions of Abelian surface and quadratic forms
Rank 2 wall-crossing and the Serre correspondence
Quadratic solutions of quadratic forms
![QR code for arXiv:1703.03049 [math.AG]](http://oss.arxitics.com/images/favicon.svg)