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arXiv · 1012.3260

The diagonal of tropical matroid varieties and cycle intersections

Georges Francois·Johannes Rau
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Abstract

We define an intersection product of tropical cycles on matroid varieties (via cutting out the diagonal) and show that it is well-behaved. In particular, this enables us to intersect cycles on moduli spaces of tropical rational marked curves $M_{0,n}$ and $M_{0,n}(\R^r, d)$. This intersection product can be extended to smooth varieties (whose local models are matroid varieties). We also study pull-backs of cycles and rational equivalence.

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Georges Francois, Johannes Rau. 2010-12-15. The diagonal of tropical matroid varieties and cycle intersections. https://doi.org/10.1007/s13348-012-0072-1

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