Exploring Ethnomathematics: Understanding Lobachevsky Geometry through Traditional Fishing Tools of the Bengkulu People

ASM Sc. J., 21(1), 2026

Published on March 17, 2026

https://doi.org/10.32802/asmscj.2026.0265

Author: Abdurrobbil Falaq Dwi Anggoro, Wardono Wardono, Scolastika Mariani, Bambang Eko Susilo

Abstract

This research bridges a gap in ethnomathematics by exploring non -Euclidean geometry through local culture. We demonstrate that the abstract concepts of Lobachevsky geometry can be intuitively understood using bubu, a traditional Bengkulu fishing trap. This study enriches Indonesian ethnomathematics and provides a pedagogical framework for teaching advanced math. Analysis of the bubu's internal structure reveals hyperbolic characteristics that embody the Lobachevsky Axiom of Parallelism. This axiom, which states that through a point outside a line there are at least two lines parallel to it, is visually reflected in the arrangement of the trap's blades. Our findings show that students grasp the Lobachevsky Parallelism Theorem not through formal proof, but as a conceptual discovery. They logically conclude that if the axiom allows for ‘at least two parallel lines’, then in hyperbolic space, the number must be ‘infinite’. This cognitive process proves how cultural contexts like the bubu can be a powerful learning medium for visualising and understanding complex mathematical principles.

Keywords: Axiom of parallelism, Bengkulu culture, Ethnomathematics, Lobachevsky geometry, Parallel Theorem