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arXiv:2508.07986

Proton-proton scattering on a quantum computer

Ratna Khadka, Gautam Rupak

Published Aug 11, 2025• 0 citations
arXivHTMLPDF

Abstract

Scattering of charged particles is ubiquitous in nuclear physics. We calculate the proton-proton $s$-wave phase shift at low energy relevant to solar physics. The phase shift is calculated from the ratio of the regular and irregular solutions to the radial Schrödinger equation on a hard spherical wall boundary for the ground state. The ground state energy is calculated using a hybrid quantum-classical variational algorithm. A theory with short-ranged nuclear interaction in the presence of the long-ranged Coulomb force is used to describe the scattering. The theory is discretized on a spatial lattice for adaptation to the quantum computer in the second quantized language. The phase shifts at low momenta are accurately reproduced.

DOI
10.48550/arxiv.2508.07986

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