Let be an algebraic torus over an algebraically closed field, let be a smooth closed subvariety of a -toric variety such that is not empty, and let be the arc scheme of . We consider a tropicalization map on , the set of arcs of that do not factor through . We show that each fiber of this tropicalization map is a constructible subset of and therefore has a motivic volume. We prove that if has a compactification with simple normal crossing boundary, then the generating function for these motivic volumes is rational, and we express this rational function in terms of certain lattice maps constructed in Hacking, Keel, and Tevelev's theory of geometric tropicalization. We explain how this result, in particular, gives a formula for Denef and Loeser's motivic zeta function of a polynomial. To further understand this formula, we also determine precisely which lattice maps arise in the construction of geometric tropicalization.
Cite this article
Jeremy Usatine, Motivic volumes of fibers of tropicalization. Port. Math. 77 (2020), no. 1, pp. 73–110DOI 10.4171/PM/2045