<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-04-17T15:53:48Z</responseDate><request verb="GetRecord" identifier="oai:www.recercat.cat:2072/479732" metadataPrefix="oai_dc">https://recercat.cat/oai/request</request><GetRecord><record><header><identifier>oai:recercat.cat:2072/479732</identifier><datestamp>2025-07-29T23:34:26Z</datestamp><setSpec>com_2072_98</setSpec><setSpec>col_2072_378192</setSpec></header><metadata><oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
   <dc:title>Newton-Okounkov bodies and Picard numbers on surfaces</dc:title>
   <dc:creator>Moyano Fernández, Julio José 4u Universitat Jaume I. Departamento de Matemática</dc:creator>
   <dc:creator>Nickel, Matthias</dc:creator>
   <dc:creator>Roé Vellvé, Joaquim</dc:creator>
   <dc:subject>Valuation</dc:subject>
   <dc:subject>Blowup</dc:subject>
   <dc:subject>Newton-Okounkov body</dc:subject>
   <dc:subject>Algebraic surface</dc:subject>
   <dc:subject>Picard number</dc:subject>
   <dc:description>We study the shapes of all Newton-Okounkov bodies ∆v(D) of a given big divisor D on a surface S with respect to all rank 2 valuations v of K(S). We obtain upper bounds for, and in many cases we determine exactly, the possible numbers of vertices of the bodies ∆v(D). The upper bounds are expressed in terms of Picard numbers and they are birationally invariant, as they do not depend on the model S˜ where the valuation v becomes a flag valuation. We also conjecture that the set of all Newton-Okounkov bodies of a single ample divisor D determines the Picard number of S, and prove that this is the case for Picard number 1, by an explicit characterization of surfaces of Picard number 1 in terms of Newton-Okounkov bodies.</dc:description>
   <dc:date>2025</dc:date>
   <dc:type>Article</dc:type>
   <dc:identifier>https://ddd.uab.cat/record/304450</dc:identifier>
   <dc:identifier>urn:10.5565/PUBLMAT6912501</dc:identifier>
   <dc:identifier>urn:oai:ddd.uab.cat:304450</dc:identifier>
   <dc:identifier>urn:oai:raco.cat:article/433253</dc:identifier>
   <dc:identifier>urn:articleid:20144350v69n1p3</dc:identifier>
   <dc:identifier>urn:oai:egreta.uab.cat:publications/57443c68-7c83-4e84-8534-b72ceda78e99</dc:identifier>
   <dc:language>eng</dc:language>
   <dc:relation>;</dc:relation>
   <dc:relation>Publicacions matemàtiques ; Vol. 69 Núm. 1 (2025), p. 3-25</dc:relation>
   <dc:rights>open access</dc:rights>
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   <dc:rights>https://rightsstatements.org/vocab/InC/1.0/</dc:rights>
   <dc:format>application/pdf</dc:format>
   <dc:publisher/>
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