arXiv subjects

Tanja Becker

Publications and source records attributed to Tanja Becker.

3 recordsLinked to original sources

arXiv2017

Moduli spaces of (G,h)-constellations

Given an infinite reductive group G acting on an affine scheme X over C and a Hilbert function h: Irr G \to N_0, we construct the moduli space M_θ(X) of θ-stable (G,h)-constellations on X, which is a generalization of the invariant Hilbert scheme after Alexeev and Brion and an analogue of the moduli space of θ-stable G-constellations for finite groups introduced by Craw and Ishii. Our construction of a morphism M_θ(X) \to X//G makes this moduli space a candidate for a resolution of singularities of the quotient X//G.

math.AG↗

arXiv2010

An example of an Sl_2-Hilbert scheme with multiplicities

We determine the invariant Hilbert scheme of the zero fibre of the moment map of an action of Sl_2 on (C^2)^6 as one of the first examples of invariant Hilbert schemes with multiplicities. While doing this, we present a general procedure how to realise the calculation of invariant Hilbert schemes, which have been introduced by Alexeev and Brion. We also consider questions of smoothness and connectedness and thereby show that our Hilbert scheme gives a resolution of singularities of the symplectic reduction of the action.

math.AG↗

arXiv2009

On the Existence of Symplectic Resolutions of Symplectic Reductions

We compute the symplectic reductions for the action of Sp_2n on several copies of C^2n and for all coregular representations of Sl_2. If it exists we give at least one symplectic resolution for each example. In the case Sl_2 acting on sl_2+C^2 we obtain an explicit description of Fu's and Namikawa's example of two non-equivalent symplectic resolutions connected by a Mukai flop.

math.AG↗