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DOE OSTI · 2507157

Maximally entangled gluons for any x

Hatta, Yoshitaka [Brookhaven National Laboratory (BNL), Upton, NY (United States). RIKEN Research Center] (ORCID:0000000168803238)·Montgomery, Jake [Stony Brook Univ., NY (United States)] (ORCID:0000000317151107)
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Abstract

Individual quarks and gluons at small x inside an unpolarized hadron can be regarded as Bell states in which qubits in the spin and orbital angular momentum spaces are maximally entangled. Using the machinery of quantum information science, we generalize this observation to all values 0 < x <1 and describe gluons (but not quarks) as maximally entangled states between a qubit and a qudit. We introduce the conditional probability distribution P⁡(l z |s z ) of a gluon’s orbital angular momentum l z given its helicity s z . Restricting to the three states l z =0,±1, which constitute a qutrit, we explicitly compute P as a function of x.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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BibTeXRIS

Hatta, Yoshitaka [Brookhaven National Laboratory (BNL), Upton, NY (United States). RIKEN Research Center] (ORCID:0000000168803238), Montgomery, Jake [Stony Brook Univ., NY (United States)] (ORCID:0000000317151107). 2025-01-22. Maximally entangled gluons for any x. https://doi.org/10.1103/physrevd.111.014024

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