<?xml version="1.0" encoding="UTF-8"?>

<modsCollection xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.loc.gov/mods/v3" xsi:schemaLocation="http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-3.xsd">
<mods version="3.3">

<genre>preprint</genre>

<titleInfo><title>Tropical double ramification loci</title></titleInfo>





<name type="personal">
  <namePart type="given">Martin</namePart>
  <namePart type="family">Ulirsch</namePart>
  <role><roleTerm type="text">author</roleTerm> </role><identifier type="local">114697</identifier></name>
<name type="personal">
  <namePart type="given">Dmitry</namePart>
  <namePart type="family">Zakharov</namePart>
  <role><roleTerm type="text">author</roleTerm> </role></name>














<abstract lang="eng">Motivated by the realizability problem for principal tropical divisors with a fixed ramification profile, we explore the tropical geometry of the double ramification locus in $\mathcal{M}_{g,n}$.There are two ways to define a tropical analogue of the double ramification locus: one as a locus of principal divisors, the other as a locus of finite effective ramified covers of a tree. We show that both loci admit a structure of a generalized cone complex in $M_{g,n}^{trop}$, with the latter contained in the former. We prove that the locus of principal divisors has cones of codimension zero in $M_{g,n}^{trop}$, while the locus of ramified covers has the expected codimension $g$. This solves the deformation-theoretic part of the realizability problem for principal divisors, reducing it to the so-called Hurwitz existence problem for covers of a fixed ramification type.</abstract>

<originInfo><dateIssued encoding="w3cdtf">2019</dateIssued>
</originInfo>
<language><languageTerm authority="iso639-2b" type="code">eng</languageTerm>
</language>



<relatedItem type="host"><titleInfo><title>arXiv:1910.01499</title></titleInfo>
  <identifier type="arXiv">1910.01499</identifier>
<part>
</part>
</relatedItem>


<extension>
<bibliographicCitation>
<mla>Ulirsch, Martin, and Dmitry Zakharov. “Tropical Double Ramification Loci.” &lt;i&gt;ArXiv:1910.01499&lt;/i&gt;, 2019.</mla>
<bibtex>@article{Ulirsch_Zakharov_2019, title={Tropical double ramification loci}, journal={arXiv:1910.01499}, author={Ulirsch, Martin and Zakharov, Dmitry}, year={2019} }</bibtex>
<ama>Ulirsch M, Zakharov D. Tropical double ramification loci. &lt;i&gt;arXiv:191001499&lt;/i&gt;. Published online 2019.</ama>
<ieee>M. Ulirsch and D. Zakharov, “Tropical double ramification loci,” &lt;i&gt;arXiv:1910.01499&lt;/i&gt;. 2019.</ieee>
<apa>Ulirsch, M., &amp;#38; Zakharov, D. (2019). Tropical double ramification loci. In &lt;i&gt;arXiv:1910.01499&lt;/i&gt;.</apa>
<chicago>Ulirsch, Martin, and Dmitry Zakharov. “Tropical Double Ramification Loci.” &lt;i&gt;ArXiv:1910.01499&lt;/i&gt;, 2019.</chicago>
<short>M. Ulirsch, D. Zakharov, ArXiv:1910.01499 (2019).</short>
</bibliographicCitation>
</extension>
<recordInfo><recordIdentifier>66322</recordIdentifier><recordCreationDate encoding="w3cdtf">2026-07-08T06:49:12Z</recordCreationDate><recordChangeDate encoding="w3cdtf">2026-07-08T06:49:19Z</recordChangeDate>
</recordInfo>
</mods>
</modsCollection>
