Degenerations of Grassmannians via Lattice Configurations

Degenerations of Surface Scrolls and the Gromov-Witten Invariants of Grassmannians

We describe an algorithm for computing certain characteristic numbers of rational normal surface scrolls using degenerations. As a corollary we obtain an efficient method for computing the corresponding Gromov-Witten invariants of the Grassmannians of lines.

Efficient Computation of Resonance Varieties via Grassmannians

Associated to the cohomology ring A of the complement X(A) of a hyperplane arrangement A in C are the resonance varieties R(A). The most studied of these is R(A), which is the union of the tangent cones at 1 to the characteristic varieties of π1(X(A)). R(A) may be described in terms of Fitting ideals, or as the locus where a certain Ext module is supported. Both these descriptions give obvious ...

Progress on Riemann existence via degenerations

Sampling biased lattice configurations using exponential metrics

Monotonic surfaces spanning finite regions of Zd arise in many contexts, including DNA-based self-assembly, card-shuffling and lozenge tilings. We explore how we can sample these surfaces when the distribution is biased to favor higher surfaces. We show that a natural local chain is rapidly mixing with any bias for regions in Z2, and for bias λ > d2 in Zd, when d > 2. Moreover, our bounds on th...

Resolving Exceptional Configurations in Quenched Lattice QCD

a Institut für Theoretische Physik, Universität Regensburg, D-93040 Regensburg b Deutsches Elektronen-Synchrotron DESY and NIC, D-15735 Zeuthen c Institut für Physik, Humboldt-Universität zu Berlin, D-10115 Berlin d Institut für Theoretische Physik, Freie Universität Berlin, D-14195 Berlin e Deutsches Elektronen-Synchrotron DESY, D-22603 Hamburg f Dipartimento di Fisica, Università di Pisa, I-5...