
Proof of the Nonexistence of an Algorithm That Tells If a Point Is on a Closed Set’s Boundary or Exterior
- 1 Valley Christian High School, San Jose, 95111, CA, USA
- 2 University of Leeds, Leeds, LS2 9JT, UK
* Author to whom correspondence should be addressed.
Abstract
This study investigates the connection between the undecidability of certain sets and the problem of determining the position of a point relative to the boundary or exterior of a closed set. We introduce a new algorithm, referred to as Algorithm A, which generates a closed set at regular intervals. By employing a reductio ad absurdum argument, we demonstrate that no algorithm exists that can consistently determine whether a point lies on the boundary or in the exterior of a closed set. This finding highlights the limitations of algorithmic approaches in the context of constructive mathematics.
Keywords
Algorithm, undecidable, closed set
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Cite this article
Fan,J.;Li,J. (2025). Proof of the Nonexistence of an Algorithm That Tells If a Point Is on a Closed Set’s Boundary or Exterior. Theoretical and Natural Science,108,88-91.
Data availability
The datasets used and/or analyzed during the current study will be available from the authors upon reasonable request.
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Volume title: Proceedings of the 4th International Conference on Computing Innovation and Applied Physics
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