5 papers
Saturation of algebraic surfaces
Agnieszka Bodzenta, Tomasz PeÅka, Dario WeiÃmann
The saturation of an algebraic surface is the maximal open embedding with complement of dimension zero. For schemes, it was introduced by the first named author and A. Bondal who a…
The Hitchin morphism for K-trivial varieties
Aryaman Patel, Dario Weissmann
We study the Hitchin morphism for higher dimensional varieties and show that, for a certain class of varieties which we call r-small, the set-theoretic image of the Hitchin morphis…
Stratifying moduli spaces of Higgs bundles and the Hitchin morphism
Aryaman Patel, Dario Weissmann
We study the behavior of slope-stability of reflexive twisted sheaves over a normal projective variety under pullback along a cover. Slope-stability is always preserved if the…
There are no exotic compact moduli of sheaves on a curve
Andres Fernandez Herrero, Dario Weissmann, Xucheng Zhang
We study moduli of coherent sheaves of some given degree and positive rank on a curve. We show that there is only one nonempty open condition on families of sheaves that yields a u…
Distinguishing Algebraic Spaces from Schemes
Andres Fernandez Herrero, Dario WeiÃmann, Xucheng Zhang
We introduce local invariants of algebraic spaces and stacks which measure how far they are from being a scheme. Using these invariants, we develop mostly topological criteria to d…