16 citations · 57 across the 30 of their papers we have counts for
35 papers
Exceptional sequences of line bundles on projective bundles
Klaus Altmann, Andreas Hochenegger, Frederik Witt
For a vector bundle we investigate exceptional sequences of line bundles on the total space of the projectivisation . In…
On the finite generation of valuation semigroups on toric surfaces
Klaus Altmann, Christian Haase, Alex Küronya +2
We provide a combinatorial criterion for the finite generation of a valuation semigroup associated with an ample divisor on a smooth toric surface and a non-toric valuation of maxi…
The structure of exceptional sequences on toric varieties of Picard rank two
Klaus Altmann, Frederik Witt
For a smooth projective toric variety of Picard rank two we classify all exceptional sequences of invertible sheaves which have maximal length. In particular, we prove that unlike…
Exceptional sequences of 8 line bundles on (P^1)^3
Klaus Altmann, Martin Altmann
We investigate maximal exceptional sequences of line bundles on (P^1)^3, i.e. those consisting of 2^r elements. For r=3 we show that they are always full, meaning that they generat…
Extensions of toric line bundles
Klaus Altmann, Amelie Flatt, Lutz Hille
For any two nef line bundles F and G on a toric variety X represented by lattice polyhedra P respectively Q, we present the universal equivariant extension of G by F under use of t…
Versality in toric geometry
Klaus Altmann, Alexandru Constantinescu, Matej Filip
We study deformations of affine toric varieties. The entire deformation theory of these singularities is encoded by the so-called versal deformation. The main goal of our paper is…