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Expanding reverse mathematics with multiple viewpoints

Research Project

Project/Area Number 16K17640
Research Category

Grant-in-Aid for Young Scientists (B)

Allocation TypeMulti-year Fund
Research Field Foundations of mathematics/Applied mathematics
Research InstitutionJapan Advanced Institute of Science and Technology

Principal Investigator

Yokoyama Keita  北陸先端科学技術大学院大学, 先端科学技術研究科, 講師 (10534430)

Project Period (FY) 2016-04-01 – 2020-03-31
Project Status Completed (Fiscal Year 2019)
Budget Amount *help
¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000)
Fiscal Year 2018: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2017: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
Fiscal Year 2016: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Keywords数理論理学 / 証明論 / 逆数学 / 算術 / 数学基礎論 / ラムゼイの定理 / 組み合わせ論 / 計算可能性理論 / 計算量理論 / 証明の長さ / 組み合わせ命題 / Ekelandの定理 / クリプキモデル / 指標関数 / 原始再帰的関数 / 組み合わせ理論 / 計算可能性 / 超準モデル
Outline of Final Research Achievements

In this project, we investigated the complexity and difficulty of mathematical theorems from the view point of reverse mathematics. Especially, we developed some new techniques to analyze the strength of combinatorial principles such as Ramsey's theorem, and solved a long-standing open problem on the proof-theoretic strength of Ramsey's theorem for pairs.
Besides the above, we introduced some arguments to apply the above result and related techniques to the termination analysis, the study of sizes of proofs, found a new phenomenon on the reverse mathematical study of functional analysis, and expanded the field of reverse mathematics with those new points of view.

Academic Significance and Societal Importance of the Research Achievements

2次元ラムゼイの定理の証明論的強さにおける長年の問題の解決とそのための手法の導入は逆数学研究におけるマイルストーンとなり、逆数学や証明論分野の国際会議で関連する多くの話題が取り上げられたほか、ウエブジャーナル Quanta Magazine でも取り上げられた。また、上の結果により、2次元ラムゼイの定理の強さがヒルベルトの還元主義プログラムの視点で十分弱いということが解明されたため、この結果の哲学的意味についても議論がなされた。

Report

(5 results)
  • 2019 Annual Research Report   Final Research Report ( PDF )
  • 2018 Research-status Report
  • 2017 Research-status Report
  • 2016 Research-status Report
  • Research Products

    (50 results)

All 2019 2018 2017 2016 Other

All Int'l Joint Research (20 results) Journal Article (10 results) (of which Int'l Joint Research: 8 results,  Peer Reviewed: 9 results,  Acknowledgement Compliant: 4 results) Presentation (19 results) (of which Int'l Joint Research: 17 results,  Invited: 8 results) Remarks (1 results)

  • [Int'l Joint Research] National University of Singapore(シンガポール)

    • Related Report
      2019 Annual Research Report
  • [Int'l Joint Research] University of Warsaw(ポーランド)

    • Related Report
      2019 Annual Research Report
  • [Int'l Joint Research] University of Leeds(英国)

    • Related Report
      2018 Research-status Report
  • [Int'l Joint Research] Ghent University(ベルギー)

    • Related Report
      2018 Research-status Report
  • [Int'l Joint Research] University of Connecticut/University of Pennsylvania(米国)

    • Related Report
      2018 Research-status Report
  • [Int'l Joint Research] Fudan University(中国)

    • Related Report
      2018 Research-status Report
  • [Int'l Joint Research] National University of Singapore(シンガポール)

    • Related Report
      2018 Research-status Report
  • [Int'l Joint Research]

    • Related Report
      2018 Research-status Report
  • [Int'l Joint Research] University of Leeds(英国)

    • Related Report
      2017 Research-status Report
  • [Int'l Joint Research] University of Warsaw(ポーランド)

    • Related Report
      2017 Research-status Report
  • [Int'l Joint Research] National University of Singapore(シンガポール)

    • Related Report
      2017 Research-status Report
  • [Int'l Joint Research] Fudan University(中国)

    • Related Report
      2017 Research-status Report
  • [Int'l Joint Research] University of Pennsylvania/University of California, Berkeley(米国)

    • Related Report
      2017 Research-status Report
  • [Int'l Joint Research]

    • Related Report
      2017 Research-status Report
  • [Int'l Joint Research] University of California, Berkeley/University of Chicago(米国)

    • Related Report
      2016 Research-status Report
  • [Int'l Joint Research] University of Leeds(United Kingdom)

    • Related Report
      2016 Research-status Report
  • [Int'l Joint Research] University of Warsaw(Poland)

    • Related Report
      2016 Research-status Report
  • [Int'l Joint Research] University of Bern(Switzerland)

    • Related Report
      2016 Research-status Report
  • [Int'l Joint Research] National Univesity of Singapore(Singapore)

    • Related Report
      2016 Research-status Report
  • [Int'l Joint Research]

    • Related Report
      2016 Research-status Report
  • [Journal Article] Combinatorial principles equivalent to weak induction2019

    • Author(s)
      Caleb Davis, Denis R. Hirschfeldt, Jeffry L. Hirst, Jake Pardo, Arno Pauly and Keita Yokoyama
    • Journal Title

      Computability

      Volume: - Issue: 3-4 Pages: 1-12

    • DOI

      10.3233/com-180244

    • Related Report
      2019 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] A parameterized halting problem, the linear time hierarchy, and the MRDP theorem2018

    • Author(s)
      Yijia Chen, Moritz Muller and Keita Yokoyama
    • Journal Title

      Proceedings of the 33rd Annual ACM/IEEE Symposium on Logic in Computer Science

      Volume: - Pages: 235-244

    • DOI

      10.1145/3209108.3209155

    • Related Report
      2018 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] The proof-theoretic strength of Ramsey's theorem for pairs and two colors2018

    • Author(s)
      Ludovic Patey and Keita Yokoyama
    • Journal Title

      Advances in Mathematics

      Volume: 330 Pages: 1034-1070

    • DOI

      10.1016/j.aim.2018.03.035

    • NAID

      120006874931

    • Related Report
      2018 Research-status Report 2017 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] The strength of Ramsey's theorem for pairs and arbitrarily many colors2018

    • Author(s)
      Theodore A. Slaman and Keita Yokoyama
    • Journal Title

      Journal of Symbolic Logic

      Volume: 83 Issue: 04 Pages: 1610-1617

    • DOI

      10.1017/jsl.2018.19

    • Related Report
      2018 Research-status Report 2017 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] The strength of SCT soundness2018

    • Author(s)
      Emanuele Frittaion, Florian Pelupessy, Silvia Steila and Keita Yokoyama
    • Journal Title

      Journal of Logic and Computation

      Volume: 印刷中 Issue: 6 Pages: 1217-1242

    • DOI

      10.1093/logcom/exy003

    • NAID

      120006725405

    • Related Report
      2018 Research-status Report 2017 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Recent studies on the proof-theoretic strength of Ramsey's theorem for pairs2017

    • Author(s)
      Keita Yokoyama
    • Journal Title

      RIMS Kokyuroku

      Volume: 2050 Pages: 67-76

    • Related Report
      2017 Research-status Report
  • [Journal Article] The strength of the SCT criterion2017

    • Author(s)
      Emanuele Frittaion, Silvia Steila and Keita Yokoyama
    • Journal Title

      Lecture Notes in Computer Science

      Volume: 10185

    • Related Report
      2016 Research-status Report
    • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
  • [Journal Article] Reverse mathematical bounds for the Termination Theorem2016

    • Author(s)
      Silvia Steila and Keita Yokoyama
    • Journal Title

      Annals of Pure and Applied Logic

      Volume: 167 Issue: 12 Pages: 1213-1241

    • DOI

      10.1016/j.apal.2016.06.001

    • NAID

      120006478232

    • Related Report
      2016 Research-status Report
    • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
  • [Journal Article] On principles between Σ1- and Σ2-induction, and monotone enumerations2016

    • Author(s)
      Alexander P. Kreuzer and Keita Yokoyama
    • Journal Title

      Journal of Mathematical Logic

      Volume: 16 Issue: 01 Pages: 1650004-1650004

    • DOI

      10.1142/s0219061316500045

    • Related Report
      2016 Research-status Report
    • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
  • [Journal Article] Notes on various versions of Friedman's self-embedding theorem2016

    • Author(s)
      Keita Yokoyama
    • Journal Title

      in;Patrick Cegielski, Ali Enayat, and Roman Kossak (eds.): Studies in Weak Arithmetics

      Volume: 3

    • Related Report
      2016 Research-status Report
    • Peer Reviewed / Acknowledgement Compliant
  • [Presentation] Weihrauch degrees of numerical problems2019

    • Author(s)
      Keita Yokoyama
    • Organizer
      Computability Theory and Foundations of Mathematics 2019
    • Related Report
      2018 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] First-order parts of Weihrauch degrees2019

    • Author(s)
      Keita Yokoyama
    • Organizer
      Third Workshop on Mathematical Logic and its Applica- tions,
    • Related Report
      2018 Research-status Report
    • Int'l Joint Research
  • [Presentation] Ramsey’s theorem and sizes of proofs2018

    • Author(s)
      Keita Yokoyama
    • Organizer
      Workshop on Ramsey Theory and Computability
    • Related Report
      2018 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Approaching the first-order strength of Hindman's theorem2018

    • Author(s)
      Keita Yokoyama
    • Organizer
      Workshop on Computability Theory and Foundations of Mathematics 2018
    • Related Report
      2018 Research-status Report
    • Int'l Joint Research
  • [Presentation] Ekeland’s variational principle in reverse mathematics2018

    • Author(s)
      Keita Yokoyama
    • Organizer
      Symposium on Advances in Mathematical Logic 2018
    • Related Report
      2018 Research-status Report
    • Int'l Joint Research
  • [Presentation] Ramsey's theorem in arithmetic2018

    • Author(s)
      Keita Yokoyama
    • Organizer
      2018 Winter Meeting of the Association of Symbolic Logic
    • Related Report
      2017 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Konig's lemma for a tree which has at most finitely many paths in reverse mathematics2017

    • Author(s)
      横山啓太
    • Organizer
      日本数学会
    • Place of Presentation
      首都大学東京(東京都八王子市)
    • Year and Date
      2017-03-24
    • Related Report
      2016 Research-status Report
  • [Presentation] On the first-order part of Ramsey's theorem for pairs2017

    • Author(s)
      Keita Yokoyama
    • Organizer
      Computability Theory and Foundations of Mathematics 2017
    • Related Report
      2017 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] On the first-order strength of Ramsey's theorem in reverse mathematics2017

    • Author(s)
      Keita Yokoyama
    • Organizer
      Logic Colloquium 2017
    • Related Report
      2017 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Caristi's fixed point theorem in reverse mathematic2017

    • Author(s)
      Keita Yokoyama
    • Organizer
      Twelfth International Conference on Computability, Complexity and Randomness (CCR 2017)
    • Related Report
      2017 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Generalized indicator and forcing2017

    • Author(s)
      Keita Yokoyama
    • Organizer
      Oberwolfach Workshop: Mathematical Logic: Proof Theory, Constructive Mathematics
    • Related Report
      2017 Research-status Report
    • Int'l Joint Research
  • [Presentation] On the Proof-Theoretic Strength of Ramsey's Theorem for Pairs2016

    • Author(s)
      Keita Yokoyama
    • Organizer
      2016 NFSC-JSPS computer science/joint research workshop
    • Place of Presentation
      しいのき迎賓館(石川県金沢市)
    • Year and Date
      2016-12-15
    • Related Report
      2016 Research-status Report
    • Int'l Joint Research
  • [Presentation] Computable analysis and reverse mathematics2016

    • Author(s)
      Keita Yokoyama
    • Organizer
      Algorithmic Randomness Interacts with Analysis and Ergodic Theory
    • Place of Presentation
      The Casa Matematica Oaxaca (CMO), Mexico
    • Year and Date
      2016-12-07
    • Related Report
      2016 Research-status Report
    • Int'l Joint Research
  • [Presentation] On the Proof-Theoretic Strength of Ramsey's Theorem for Pairs2016

    • Author(s)
      Keita Yokoyama
    • Organizer
      Mathematical Logic and Its Applications
    • Place of Presentation
      京都大学(京都府京都市)
    • Year and Date
      2016-09-26
    • Related Report
      2016 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] On the proof-theoretic strength of Ramsey's theorem for pairs2016

    • Author(s)
      横山啓太
    • Organizer
      日本数学会
    • Place of Presentation
      関西大学(大阪府吹田市)
    • Year and Date
      2016-09-18
    • Related Report
      2016 Research-status Report
  • [Presentation] Proof-theoretic strength and indicator arguments2016

    • Author(s)
      Keita Yokoyama
    • Organizer
      Workshop on Mathematical Logic and its Applications
    • Place of Presentation
      京都大学(京都府京都市)
    • Year and Date
      2016-09-16
    • Related Report
      2016 Research-status Report
    • Int'l Joint Research
  • [Presentation] Nonstandard methods in combinatorics2016

    • Author(s)
      Keita Yokoyama
    • Organizer
      The 11th AIMS Conference on Dynamical Systems
    • Place of Presentation
      Orlando, Florida, USA
    • Year and Date
      2016-07-04
    • Related Report
      2016 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] On the first-order strength of Ramsey's theorem for pairs and finitely many colors2016

    • Author(s)
      Keita Yokoyama
    • Organizer
      Association for Symbolic Logic 2016 Annual North American Meeting
    • Place of Presentation
      University of Connecticut, Storrs, USA
    • Year and Date
      2016-05-25
    • Related Report
      2016 Research-status Report
    • Int'l Joint Research
  • [Presentation] The proof-theoretic strength of Ramsey's theorem for pairs2016

    • Author(s)
      Keita Yokoyama
    • Organizer
      Mathematics for Computation
    • Place of Presentation
      Lower Bavaria, DE, Germany
    • Year and Date
      2016-05-09
    • Related Report
      2016 Research-status Report
    • Int'l Joint Research
  • [Remarks] 横山啓太 - 研究者 - Research map

    • URL

      http://researchmap.jp/read0145758/

    • Related Report
      2016 Research-status Report

URL: 

Published: 2016-04-21   Modified: 2022-02-16  

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