Unified Description of Polarized and Unpolarized Quark Distributions in the Proton

TL;DR

This paper introduces a unified approach using gauge-gravity correspondence and light-front holography to describe polarized and unpolarized quark distributions in the proton, predicting a sign reversal in polarized down-quark distribution at high momentum.

Contribution

It presents a novel unified framework linking polarized and unpolarized distributions through chirality separation without extra parameters.

Findings

Predicted sign reversal of polarized down-quark distribution at x=0.8±0.03

Results align with experimental data and QCD constraints

Provides testable predictions for upcoming experiments

Abstract

We propose a unified new approach to describe polarized and unpolarized quark distributions in the proton based on the gauge-gravity correspondence, light-front holography, and the generalized Veneziano model. We find that the spin-dependent quark distributions are uniquely determined in terms of the unpolarized distributions by chirality separation without the introduction of additional free parameters. The predictions are consistent with existing experimental data and agree with perturbative QCD constraints at large longitudinal momentum $x$. In particular, we predict the sign reversal of the polarized down-quark distribution in the proton at $x=0.8\pm0.03$, a key property of nucleon substructure which will be tested very soon in upcoming experiments.