A tractability gap beyond nim-sums: It's hard to tell whether a bunch of superstars are losers.

Saved in:
Bibliographic Details
Title: A tractability gap beyond nim-sums: It's hard to tell whether a bunch of superstars are losers.
Authors: Burke, Kyle1 (AUTHOR) kburke@flsouthern.edu, Ferland, Matthew2 (AUTHOR) ferlandm@dickinson.edu, Huntemann, Svenja1,3 (AUTHOR) svenja.huntemann@msvu.ca, Teng, Shang-Hua4 (AUTHOR) shanghua@usc.edu
Source: Theoretical Computer Science. Feb2026, Vol. 1062, pN.PAG-N.PAG. 1p.
Subjects: Game theory, Computational complexity, Games
Abstract: In this paper, we address a natural question at the intersection of combinatorial game theory and computational complexity: "Can a sum of simple tepid games in canonical form be intractable?" To resolve this fundamental question, we consider superstars , positions first introduced in Winning Ways where all options are nimbers. Extending Morris' classic result with hot games to tepid games, we prove that disjunctive sums of superstars are intractable to solve. This is striking as sums of nimbers can be computed in linear time. Our analysis shows that the game Paint Can is intractable and also yields a new intractable game, Blackout. We present web-playable versions of both games. [ABSTRACT FROM AUTHOR]
Copyright of Theoretical Computer Science is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
FullText Text:
  Availability: 0
Header DbId: egs
DbLabel: Engineering Source
An: 190262920
AccessLevel: 6
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: A tractability gap beyond nim-sums: It's hard to tell whether a bunch of superstars are losers.
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Burke%2C+Kyle%22">Burke, Kyle</searchLink><relatesTo>1</relatesTo> (AUTHOR)<i> kburke@flsouthern.edu</i><br /><searchLink fieldCode="AR" term="%22Ferland%2C+Matthew%22">Ferland, Matthew</searchLink><relatesTo>2</relatesTo> (AUTHOR)<i> ferlandm@dickinson.edu</i><br /><searchLink fieldCode="AR" term="%22Huntemann%2C+Svenja%22">Huntemann, Svenja</searchLink><relatesTo>1,3</relatesTo> (AUTHOR)<i> svenja.huntemann@msvu.ca</i><br /><searchLink fieldCode="AR" term="%22Teng%2C+Shang-Hua%22">Teng, Shang-Hua</searchLink><relatesTo>4</relatesTo> (AUTHOR)<i> shanghua@usc.edu</i>
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="JN" term="%22Theoretical+Computer+Science%22">Theoretical Computer Science</searchLink>. Feb2026, Vol. 1062, pN.PAG-N.PAG. 1p.
– Name: Subject
  Label: Subjects
  Group: Su
  Data: <searchLink fieldCode="DE" term="%22Game+theory%22">Game theory</searchLink><br /><searchLink fieldCode="DE" term="%22Computational+complexity%22">Computational complexity</searchLink><br /><searchLink fieldCode="DE" term="%22Games%22">Games</searchLink>
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: In this paper, we address a natural question at the intersection of combinatorial game theory and computational complexity: "Can a sum of simple tepid games in canonical form be intractable?" To resolve this fundamental question, we consider superstars , positions first introduced in Winning Ways where all options are nimbers. Extending Morris' classic result with hot games to tepid games, we prove that disjunctive sums of superstars are intractable to solve. This is striking as sums of nimbers can be computed in linear time. Our analysis shows that the game Paint Can is intractable and also yields a new intractable game, Blackout. We present web-playable versions of both games. [ABSTRACT FROM AUTHOR]
– Name: AbstractSuppliedCopyright
  Label:
  Group: Ab
  Data: <i>Copyright of Theoretical Computer Science is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.)
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=egs&AN=190262920
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1016/j.tcs.2025.115656
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 1
        StartPage: N.PAG
    Subjects:
      – SubjectFull: Game theory
        Type: general
      – SubjectFull: Computational complexity
        Type: general
      – SubjectFull: Games
        Type: general
    Titles:
      – TitleFull: A tractability gap beyond nim-sums: It's hard to tell whether a bunch of superstars are losers.
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Burke, Kyle
      – PersonEntity:
          Name:
            NameFull: Ferland, Matthew
      – PersonEntity:
          Name:
            NameFull: Huntemann, Svenja
      – PersonEntity:
          Name:
            NameFull: Teng, Shang-Hua
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 02
              M: 02
              Text: Feb2026
              Type: published
              Y: 2026
          Identifiers:
            – Type: issn-print
              Value: 03043975
          Numbering:
            – Type: volume
              Value: 1062
          Titles:
            – TitleFull: Theoretical Computer Science
              Type: main
ResultId 1