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        <datestamp>2024-03-06T10:58:28Z</datestamp>
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          <dc:title>Oracle with P = NP ∩ coNP, but No Many-One Completeness in UP, DisjNP, and DisjCoNP</dc:title>
          <dc:creator>Ehrmanntraut, Anton</dc:creator>
          <dc:creator>Egidy, Fabian</dc:creator>
          <dc:creator>Glaßer, Christian</dc:creator>
          <dc:subject>computational complexity</dc:subject>
          <dc:subject>promise classes</dc:subject>
          <dc:subject>proof complexity</dc:subject>
          <dc:subject>complete sets</dc:subject>
          <dc:subject>oracle construction</dc:subject>
          <dc:description>We construct an oracle relative to which P = NP ∩ coNP, but there are no many-one complete sets in UP, no many-one complete disjoint NP-pairs, and no many-one complete disjoint coNP-pairs.&#13;
This contributes to a research program initiated by Pudlák [P. Pudlák, 2017], which studies incompleteness in the finite domain and which mentions the construction of such oracles as open problem. The oracle shows that NP ∩ coNP is indispensable in the list of hypotheses studied by Pudlák. Hence one should consider stronger hypotheses, in order to find a universal one.</dc:description>
          <dc:publisher>Schloss Dagstuhl – Leibniz-Zentrum für Informatik</dc:publisher>
          <dc:contributor>Anton Ehrmanntraut and Fabian Egidy and Christian Glaßer</dc:contributor>
          <dc:date>2022</dc:date>
          <dc:relation>Is Part Of LIPIcs, Volume 241, 47th International Symposium on Mathematical Foundations of Computer Science (MFCS 2022)</dc:relation>
          <dc:type>InProceedings</dc:type>
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          <dc:identifier>doi:10.4230/LIPIcs.MFCS.2022.45</dc:identifier>
          <dc:identifier>urn:nbn:de:0030-drops-168435</dc:identifier>
          <dc:identifier>https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.MFCS.2022.45</dc:identifier>
          <dc:language>eng</dc:language>
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