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 \(\mathcal M _n\) and \(\mathcal M _n^{\text{ lab}}(\Delta , \mathbb R ^r)\). 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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Acknowledgments
We are grateful to Kristin Shaw, Federico Ardila and Andreas Gathmann for many helpful discussions and comments. We would also like to thank the reviewer for useful comments and suggestions.
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G. François is supported by the Fonds national de la Recherche (FNR), Luxembourg.
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François, G., Rau, J. The diagonal of tropical matroid varieties and cycle intersections. Collect. Math. 64, 185–210 (2013). https://doi.org/10.1007/s13348-012-0072-1
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DOI: https://doi.org/10.1007/s13348-012-0072-1