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arXiv · 2102.07830

Proton mass decomposition: naturalness and interpretations

Xiangdong Ji
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Abstract

I discuss the scope and naturalness of the proton mass decomposition (or sum rule) published in PRL74, 1071 (1995) and answer a few criticisms that appeared recently in the literature, focusing particularly on its interpretation and the quantum anomalous energy contribution. I comment on the so-called frame-independent or invariant-mass decomposition from the trace of the energy-momentum tensor. I stress the importance of measuring the quantum anomalous energy through experiments. Finally, I point out a large discrepancy in the scalar radius of the nucleon extracted from vector-meson productions and lattice QCD calculations.

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Xiangdong Ji. 2021-02-15. Proton mass decomposition: naturalness and interpretations. https://arxiv.org/abs/2102.07830

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