Topology and arithmetic of resultants, I: spaces of rational maps

Benson Farb; Jesse Wolfson

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arXiv · 1506.02713

Topology and arithmetic of resultants, I: spaces of rational maps

Benson Farb·Jesse Wolfson

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Abstract

We consider the interplay of point counts, singular cohomology, \'etale cohomology, eigenvalues of the Frobenius and the Grothendieck ring of varieties for two families of varieties: spaces of rational maps and moduli spaces of marked, degree $d$ rational curves in $\mathbb{P}^n$. We deduce as special cases algebro-geometric and arithmetic refinements of topological computations of Segal, Cohen--Cohen--Mann--Milgram, Vassiliev and others.

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Benson Farb, Jesse Wolfson. 2015-06-08. Topology and arithmetic of resultants, I: spaces of rational maps. https://arxiv.org/abs/1506.02713

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