On the algebraic and topological structure of temporal graphs: A unified framework for $(f, g)$-homomorphisms and Spatio-Temporal flows

Document Type : Research Paper

Authors

1 Department of Mathematics, Semnan University, P.O. Box 35195-363, Semnan, Iran

2 Applied Mathematics and Informatics, Kyrgyz-Turkish Manas University, Bishkek, Kyrgyzstan

Abstract

Modelling complex systems where connections are transient requires a departure from static graph theory. This paper proposes a comprehensive mathematical framework for {Temporal Graphs}, extending classical concepts to capture dynamic interactions and causality. We identify fundamental limitations in static representations, specifically the "Path Existence Fallacy" and "Flow Indistinguishability." To resolve these, we introduce the novel concept of {$(f, g)$-homomorphism}, a structural mapping $f$ coupled with a temporal mapping $g$, which allows for the modelling of time dilation, contraction, and reversal within network flows. Furthermore, we define hierarchical temporal graphs (HTGs) for multi-scale analysis. Finally, we present a rigorous list of open problems in pure mathematics—ranging from temporal fixed point theory to persistent homology—and future applications in quantum computing and blockchain dynamics.

Keywords

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Articles in Press, Corrected Proof
Available Online from 12 December 2025
  • Receive Date: 04 June 2025
  • Revise Date: 06 August 2025
  • Accept Date: 28 October 2025