Energy and Spectrum of the Line Graphs of a Unit Graphs

Authors

  • Nabilah Zulkfeli Faculty of Informatics and Computing, Universiti Sultan Zainal Abidin, Tembila Campus, 22200, Besut, Terengganu, Malaysia
  • Siti Norziahidayu Amzee Zamri ᵇUniSZA Science and Medicine Foundation Centre, Universiti Sultan Zainal Abidin, Gong Badak Campus, 21310 Kuala Nerus, Terengganu, Malaysia; ᶜEast Coast Environmental Research Institute (ESERI), Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300, Kuala Terengganu, Malaysia
  • Hazzirah Izzati Mat Hassim Department of Mathematical Sciences, Faculty of Science, 81310 UTM Johor Bahru, Johor, Malaysia
  • Zahratul Amani Zakaria Faculty of Informatics and Computing, Universiti Sultan Zainal Abidin, Tembila Campus, 22200, Besut, Terengganu, Malaysia

DOI:

https://doi.org/10.11113/mjfas.v21n5.4312

Keywords:

Unit graph, line graph, graph energy; graph spectrum

Abstract

The study delves into an analysis of energy and spectral properties of the line graph, denoted as , derived from the unit graph  offering a comprehensive mathematical exploration. Then, we begin by defining key concepts such as unit graphs, line graphs, and their spectral characteristics. Our investigation involves the computation of eigenvalues and their corresponding energy values, demonstrating how the adjacency matrix influences spectral behaviour. Furthermore, we analyse how variations in graph parameters impact energy distribution and eigenvalue structure. Theoretical derivations are supported by computational results, revealing significant trends and relationships in graph energy and spectrum. By building upon existing literature and introducing new theoretical insights, this research contributes to the ongoing development of spectral graph theory, with potential applications in network analysis, mathematical chemistry, and physics. By analysing the adjacency matrices of line graphs derived from unit graphs, this paper investigates  which mean the line graphs of a unit graphs, where edges in  act as vertices in , computes eigenvalues, examines graph properties, and derives general expressions for energy and spectrum. This study focuses on integer modulo rings ,  for specific values of .

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Published

02-11-2025