Entanglement Suppression and Emergent Symmetries of Strong Interactions

Abstract

Entanglement suppression in the strong interaction S-matrix is shown to be correlated with approximate spin-flavor symmetries that are observed in low-energy baryon interactions, the Wigner SU (4) symmetry for two flavors and an SU (16) symmetry for three flavors. We conjecture that dynamical entanglement suppression is a property of the strong interactions in the infrared, giving rise to these emergent symmetries and providing powerful constraints on the nature of nuclear and hypernuclear forces in dense matter.Understanding approximate global symmetries in the strong interactions has played an important historical role in the development of the theory of Quantum Chromodynamics (QCD). Baryon number symmetry arises in QCD because it is impossible to include a marginal or relevant interaction consistent with Lorentz and gauge symmetry which violates baryon number, while the axial and vector flavor symmetries are understood to be due to the small ratio of quark masses (and their differences) to the QCD scale. The approximate low-energy SU (2n f ) spin-flavor symmetry for n f = 2, 3 flavors which relates spin-1/2 and spin-3/2 baryons can be understood as arising at leading order (LO) in the large-N c expansion, where N c is the number of colors [1,2]. In lowenergy nuclear physics, a different spin-flavor symmetry is observed in the structure of light-nuclei and their βdecay rates, namely Wigner's SU (4) symmetry, where the two spin states of the two nucleons transform as the 4-dimensional fundamental representation [3][4][5]. It has been shown that this symmetry also arises from the large-N c expansion at energies below the ∆ mass [6][7][8]. The agreement of large-N c predictions with nuclear phenomenology has been extended to higher-order interactions [9-12], three-nucleon systems [13][14][15], and to studies of hadronic parity violation [16][17][18]. Recently, however, lattice QCD computations for n f = 3 have revealed an emergent SU (16) symmetry in low-energy interactions of the baryon octet-analogous to Wigner's SU (4), but with the two spin states of the eight baryons transforming as the 16-dimensional representation of SU (16) [19]. This low energy symmetry has been lacking an explanation from QCD. In this Letter, we show that both Wigner's SU (4) symmetry for n f = 2 and SU (16) for n f = 3 correspond to fixed lines of minimal quantum entanglement in the S-matrix for baryon-baryon scattering, and we propose entanglement suppression to be a dynamical property of QCD and the origin of these emergent symmetries 1 .

Silence of Binary Kerr Black Holes

“…Given the correspondence between minimal coupling and rotating black holes, the result suggests that this feature can also be attributed to the entanglement properties of spinning black holes. Note that this phenomenon is reminiscent of what was found in strong interactions, where entanglement suppression is associated with symmetry enhancement [10].…”

“…Any deviation from unity significantly increases the relative entropy. Entanglement via S matrix.-The study of entanglement in scattering events has a long history (for recent developments, see [9][10][11][12]). After denoting the two-particle Hilbert space by H ¼ H a ⊗ H b , for each subsystem we can further divide the space into spin and momentum degrees of freedom, e.g., H a ¼ H s a ⊗ H p a .…”

The path from finite to infinite volume: Hadronic observables from lattice QCD

“…In Refs. [23,43], a similar kinked feature was observed in the correlation function of neutral pions with nonperiodic implementations of a uniform electric field with the choice of a time-dependent gauge potential.…”

“…See also Ref. [23] for an interesting recent explanation. Figure 3: Diagrammatic expansion of the coupled-channels correlation function [24].…”

Chiral symmetry breaking, entanglement, and the nucleon spin decomposition

“…Many of the generic features of the two-component model persist in more realistic state vectors: for instance, the large-N c component is always dominant due to the prominent nucleon-∆ axial transition, but not so much so that it has much of an effect on the entanglement entropy, which is always near its maximum value 4 . The valence spin content in 4 By contrast, recent work has found that entanglement in the nuclear force, as measured by the entanglement power, is minimized by the experimental data, and is very near large-Nc expectations [31].…”