Corpus ID: 119126194

# Universal families of extensions of coherent systems

@article{Tommasini2013UniversalFO,
title={Universal families of extensions of coherent systems},
author={Matteo Tommasini},
journal={arXiv: Algebraic Geometry},
year={2013}
}
We prove a result of cohomology and base change for families of coherent systems over a curve. We use that in order to prove the existence of (non-split, non-degenerate) universal families of extensions for families of coherent systems (in the spirit of the paper "Universal families of extensions" by H. Lange). Such results will be applied in subsequent papers in order to describe the wallcrossing for some moduli spaces of coherent systems.
Virtual Poincaré polynomial of the space of stable pairs supported on quintic curves
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Moduli Spaces of $\alpha$-stable Pairs and Wall-Crossing on $\mathbb{P}^2$
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• 2012
We study the wall-crossing of the moduli spaces $\mathbf{M}^\alpha (d,1)$ of $\alpha$-stable pairs with linear Hilbert polynomial $dm+1$ on the projective plane $\mathbb{P}^2$ as we alter theExpand

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