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        <datestamp>2024-03-06T10:55:56Z</datestamp>
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          <dc:title>Excluding PH Pessiland</dc:title>
          <dc:creator>Hirahara, Shuichi</dc:creator>
          <dc:creator>Santhanam, Rahul</dc:creator>
          <dc:subject>average-case complexity</dc:subject>
          <dc:subject>pseudorandomness</dc:subject>
          <dc:subject>meta-complexity</dc:subject>
          <dc:description>Heuristica and Pessiland are "worlds" of average-case complexity [Impagliazzo95] that are considered unlikely but that current techniques are unable to rule out. Recently, [Hirahara20] considered a PH (Polynomial Hierarchy) analogue of Heuristica, and showed that to rule it out, it would be sufficient to prove the NP-completeness of the problem GapMINKT^PH of estimating the PH-oracle time-bounded Kolmogorov complexity of a string.&#13;
In this work, we analogously define "PH Pessiland" to be a world where PH is hard on average but PH-computable pseudo-random generators do not exist. We unconditionally rule out PH-Pessiland in both non-uniform and uniform settings, by showing that the distributional problem of computing PH-oracle time-bounded Kolmogorov complexity of a string over the uniform distribution is complete for an (error-prone) average-case analogue of PH. Moreover, we show the equivalence between error-prone average-case hardness of PH and the existence of PH-computable pseudorandom generators.</dc:description>
          <dc:publisher>Schloss Dagstuhl – Leibniz-Zentrum für Informatik</dc:publisher>
          <dc:contributor>Shuichi Hirahara and Rahul Santhanam</dc:contributor>
          <dc:date>2022</dc:date>
          <dc:relation>Is Part Of LIPIcs, Volume 215, 13th Innovations in Theoretical Computer Science Conference (ITCS 2022)</dc:relation>
          <dc:type>InProceedings</dc:type>
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          <dc:identifier>doi:10.4230/LIPIcs.ITCS.2022.85</dc:identifier>
          <dc:identifier>urn:nbn:de:0030-drops-156819</dc:identifier>
          <dc:identifier>https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ITCS.2022.85</dc:identifier>
          <dc:language>eng</dc:language>
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