Determining the proton content with a quantum computer

TL;DR

This paper explores the use of quantum computing to determine the parton content of protons by designing variational quantum circuits, testing them on real devices, and comparing results with traditional PDFs.

Contribution

It introduces architectures of variational quantum circuits for PDFs, demonstrates their deployment on real quantum hardware, and performs a global qPDF determination from collider data.

Findings

Quantum circuits suitable for PDFs were identified.

Experiments on real quantum devices show feasibility.

Quantum-based PDFs are comparable to modern classical PDFs.

Abstract

We present a first attempt to design a quantum circuit for the determination of the parton content of the proton through the estimation of parton distribution functions (PDFs), in the context of high energy physics (HEP). The growing interest in quantum computing and the recent developments of new algorithms and quantum hardware devices motivates the study of methodologies applied to HEP. In this work we identify architectures of variational quantum circuits suitable for PDFs representation (qPDFs). We show experiments about the deployment of qPDFs on real quantum devices, taking into consideration current experimental limitations. Finally, we perform a global qPDF determination from collider data using quantum computer simulation on classical hardware and we compare the obtained partons and related phenomenological predictions involving hadronic processes to modern PDFs.