Quantum Machine Learning for Track Reconstruction

¹ Istituto Nazionale di Fisica Nucleare, sezione di Ferrara, Via Saragat 1, Ferrara, Italy,
² Physics and Earth sciences department, University of Ferrara, Via Saragat 1, Ferrara, Italy

^* e-mail: laura.cappelli@fe.infn.it
^** e-mail: matteo.argenton@unife.it

Published online: 7 October 2025

Abstract

Tracking charged particles in high-energy physics experiments is a computationally intensive task. With the advent of the High Luminosity LHC era, which is expected to significantly increase the number of proton-proton interactions per beam collision, the amount of data to be analysed will increase significantly. As a consequence, local pattern recognition algorithms suffer from scaling problems.

In this work, we investigate the possibility of using machine learning techniques in combination with quantum computing. In particular, we represent particle trajectories as a graph data structure and train a quantum graph neural network to perform global pattern recognition.

We show recent results on the application of this method, with scalability tests for increasing pileup values. We also provide insights into various aspects of code development in different quantum programming frameworks such as Pennylane and IBM Qiskit. Finally, we discuss the critical points and give an outlook of potential improvements and alternative approaches.