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Published on 6 May 2025
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Jin,E.;Li,Y.;Qian,X.;Yao,K.;Yu,S. (2025). Nonexistence of Algorithm Deciding if the Fundamental Group of an Arbitrary Constructive Compact Set is Trivial. Theoretical and Natural Science,108,38-42.
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Nonexistence of Algorithm Deciding if the Fundamental Group of an Arbitrary Constructive Compact Set is Trivial

Encheng Jin 1, Yang Li 2, Xinyang Qian 3, Kaijing Yao *,4, Siheng Yu 5
  • 1 Dalian No.24 High School Cambridge International Education Department
  • 2 College of Art and Science, New York University, New York
  • 3 Nanjing Foreign Language School, Nanjing
  • 4 Department of Mathematics, University of California, Berkeley
  • 5 No.2 High School of East China Normal University

* Author to whom correspondence should be addressed.

https://doi.org/10.54254/2753-8818/2025.22661

Abstract

In this paper, we give an introduction to the compact space under Constructive Mathematics, ultimately showing that there exist no computer programs that can always determine if a fundamental group of a constructive compact topological space is trivial or not. We will begin with the non-halting case of the programs, which shows that the fundamental group of our selected set is trivial. From here, we will explore the halting case of the programs, which can be solved by arbitrarily picking a nontrivial subset of our selected set. The main result of this section is that we can show that the algorithm is decidable due to our initial construction, while realizing its contradiction with our input. We want to show that such an algorithm doesn’t exist by employing the proof-by-contradiction method.

Keywords

compact space, constructive mathematics, fundamental group, halting problem

[1]. Turing, A. (1937). On computable numbers, with an application to the entscheidungs problem. Proceedings of the London Mathematical Society, s2-42(1).

[2]. Turing, A. (1938). On computable numbers, with an application to the entscheidungsproblem. a correction. Proceedings of the London Mathematical Society, s2-43(1).

[3]. Troelstra, A. (1977). Aspects of constructive mathematics. Studies in Logic and the Foundations of Mathematics.

[4]. Kushner, B. A. (1996). Kurt Gödel and the constructive mathematics of A.A. Markov. Lecture Notes in Logic, 50–63.

[5]. Markov, A., German, C., and Herken, R. (1958). Insolubility of the problem of homeomorphy.

[6]. Bishop, E, and Bridges, D. S. (1967). Constructive Analysis. Springer.

[7]. Bishop, E., & Beeson, M. (2013). Foundations of constructive analysis. Ishi Press International.

[8]. Kushner, B. A. (1984). Lectures on constructive mathematical analysis. London Mathematical Society.

[9]. Waaldijk, F. (2005). On the foundations of constructive mathematics – especially in relation to the theory of continuous functions. Foundations of Science, 10(3).

[10]. Poincare, H. (2010). Papers on topology: Analysis situs and its five supplements. American Mathematical Society; London Mathematical Society.

[11]. Bienvenu, L., D. D. . S. A. (2016). Generic algorithms for halting problem and optimal machines revisited. Logical Methods in Computer Science, 12(2).

[12]. Köhler, S., S. C. . Z. M. (2005). On approximating real-world halting problems. Lecture Notes in Computer Science.

Cite this article

Jin,E.;Li,Y.;Qian,X.;Yao,K.;Yu,S. (2025). Nonexistence of Algorithm Deciding if the Fundamental Group of an Arbitrary Constructive Compact Set is Trivial. Theoretical and Natural Science,108,38-42.

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The datasets used and/or analyzed during the current study will be available from the authors upon reasonable request.

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About volume

Volume title: Proceedings of the 4th International Conference on Computing Innovation and Applied Physics

Conference website: https://2025.confciap.org/
ISBN:978-1-80590-089-4(Print) / 978-1-80590-090-0(Online)
Conference date: 17 January 2025
Editor:Ömer Burak İSTANBULLU, Marwan Omar, Anil Fernando
Series: Theoretical and Natural Science
Volume number: Vol.108
ISSN:2753-8818(Print) / 2753-8826(Online)

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