Quantum algorithm for testing graph completeness

Testing graph completeness is a critical problem in computer science and network theory. Leveraging quantum computation, we present an efficient algorithm using the Szegedy quantum walk and quantum phase estimation (QPE). Our algorithm, which takes the number of nodes and the adjacency matrix as inp...

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Detalles Bibliográficos
Autores: Giordano, Sara, Martín-Delgado Alcántara, Miguel Ángel
Tipo de recurso: artículo
Fecha de publicación:2026
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/129045
Acceso en línea:https://hdl.handle.net/20.500.14352/129045
Access Level:acceso abierto
Palabra clave:519.17
004.42
539.12
Quantum computing
Quantum algorithms
Szegedy quantum walk
Quantum phase estimation
Graphs
Complete graphs
Física (Física)
Teoría de los quanta
Informática (Informática)
2212 Física Teórica
1206.01 Construcción de Algoritmos
1203.17 Informática
Descripción
Sumario:Testing graph completeness is a critical problem in computer science and network theory. Leveraging quantum computation, we present an efficient algorithm using the Szegedy quantum walk and quantum phase estimation (QPE). Our algorithm, which takes the number of nodes and the adjacency matrix as input, constructs a quantum walk operator and applies QPE to estimate its eigenvalues. These eigenvalues reveal the graph’s structural properties, enabling us to determine its completeness. We establish a relationship between the number of nodes in a complete graph and the number of marked nodes, optimizing the success probability and running time. The time complexity of our algorithm is (log2 ), where is the number of nodes of the graph. offering a clear quantum advantage over classical methods. This approach is useful in network structure analysis, evaluating classical routing algorithms, and assessing systems based on pairwise comparisons.