This paper explores the interplay between graph theory and topology by introducing a novel framework based on flexible paths in directed graphs. Extending the classical notion of monophonic paths, we define flexible graphical topologies and characterize classes of directed graphs whose associated flexible graphical topologies are discrete or indiscrete. Fundamental topological properties, including connectedness, compactness, and homeomorphism, are investigated within this framework. Based on these properties, the notions of flexible connectedness and flexible discreteness are introduced and studied. To demonstrate the applicability of the proposed framework, we considered graph representations derived from the human circulatory system. The obtained flexible graphical topological structures are analyzed to illustrate their ability to capture connectedness, flexible connectedness, and flexible discreteness in biologically inspired networks. The results showed that flexible graphical topology provides an extended mathematical framework for studying structural properties of directed networks and offers potential for future applications in biological and complex systems.
Citation: Husniyah Alzubaidi, Ljubiša D. R. Kočinac, Hakeem A. Othman. On the flexibility of monophonic paths and connectedness property: application to the human circulatory system[J]. AIMS Mathematics, 2026, 11(6): 18994-19010. doi: 10.3934/math.2026773
This paper explores the interplay between graph theory and topology by introducing a novel framework based on flexible paths in directed graphs. Extending the classical notion of monophonic paths, we define flexible graphical topologies and characterize classes of directed graphs whose associated flexible graphical topologies are discrete or indiscrete. Fundamental topological properties, including connectedness, compactness, and homeomorphism, are investigated within this framework. Based on these properties, the notions of flexible connectedness and flexible discreteness are introduced and studied. To demonstrate the applicability of the proposed framework, we considered graph representations derived from the human circulatory system. The obtained flexible graphical topological structures are analyzed to illustrate their ability to capture connectedness, flexible connectedness, and flexible discreteness in biologically inspired networks. The results showed that flexible graphical topology provides an extended mathematical framework for studying structural properties of directed networks and offers potential for future applications in biological and complex systems.
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