Maximally entangled gluons for any x

Journal Article · 21 January 2025 · Physical Review. D.

DOI: https://doi.org/10.1103/physrevd.111.014024 · OSTI ID:2507157

Hatta, Yoshitaka  ^[1]; Montgomery, Jake  ^[2]

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1. Brookhaven National Laboratory (BNL), Upton, NY (United States). RIKEN Research Center
2. Stony Brook Univ., NY (United States)

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.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP); USDOE Laboratory Directed Research and Development (LDRD) Program
• Grant/Contract Number: SC0012704; SC0024358
• OSTI ID: 2507157
• Report Number(s): BNL--227517-2025-JAAM
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 1 Vol. 111; ISSN 2470-0010
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English