Björn Selander: Stiefel–Whitney classes of curve covers

We intend to define an invariant for tamely and oddly ramified covers of Dedekind schemes, which generalises an invariant defined by Serre. This invariant will then be related to the second Stiefel–Whitney class of the push-forward of half the codifferent divisor, once again generalising and simplifying the treatment by Serre. Some background on Stiefel–Whitney classes in algebraic geometry as well as theta characteristics will also be presented.