We consider four-point functions of protected, double- and single-trace operators in the large central charge limit. We use superconformal symmetry to disentangle the contribution of protected operators in the partial wave decomposition. With this information, we fix the non-protected part of such correlators up to subleading order in the large central charge expansion. We particularly focus on the triple-trace sector of the correlator and comment on the connection to the holographic description of these correlators.

Italy

Sweden

Agnese Bissi

United States

Giulia Fardelli

Andrea Manenti

Composite operators in $$ \mathcal{N} $$ = 4 Super Yang-Mills

We study the large-charge sector of $$\mathcal{N}$$ = 4 super Yang-Mills theory (SYM) with SU($\textit{N}$) gauge group by constructing a special class of half-BPS heavy operators, termed “canonical operators”. Such operators exhibit remarkable simplicity in the large-charge ’t Hooft limit, where the dimension of the operators ∆ → ∞ with $${\Delta g}_{\text{YM}}^{2}$$ held finite. Canonical operator insertions in this regime map $$\mathcal{N}$$ = 4 SYM onto the Coulomb branch, by assigning a classical profile to the scalar fields with non-vanishing values along the diagonals given by the roots of unity. We follow a semiclassical approach to study two-point, three-point and Heavy-Heavy-Light-Light (HHLL) correlators. In particular we show that HHLL correlators in the large-charge ’t Hooft limit are computed as two-point functions in a background determined by the classical profiles. We provide consistent evidence of our findings by computing the same observables via supersymmetric localization.

United Kingdom

Augustus Brown

Francesco Galvagno

Switzerland

Alba Grassi

Cristoforo Iossa

Congkao Wen

Large charge meets semiclassics in $$\mathcal{N}$$ = 4 super Yang-Mills

Since the inception of lattice QCD, a natural definition for the Yang-Mills instanton on lattice has been long sought for. In a recent work [1], one of authors showed the natural solution has to be organized in terms of bundle gerbes in higher homotopy theory / higher category theory, and introduced the principles for such a categorical construction. To pave the way towards actual numerical implementation in the near future, nonetheless, an explicit construction is necessary. In this paper we provide such an explicit construction for SU(2) gauge theory, with technical aspects inspired by Lüscher’s 1982 geometrical construction [2]. We will see how the latter is in a suitable sense a saddle point approximation to the full categorical construction. The generalization to SU($\textit{N}$) will be discussed. The construction also allows for a natural definition of lattice Chern-Simons-Yang-Mills theory in three spacetime dimensions.

China

Peng Zhang

Jing-Yuan Chen

An explicit categorical construction of instanton density in lattice Yang-Mills theory

Recently, an exact black hole solution in non-minimal Einstein–Yang–Mills theory was obtained, and its quasinormal modes were subsequently analyzed using the JWKB approximation (Gogoi and Ponglertsakul in Eur. Phys. J. C 84:652, 2024. . [gr-qc]). However, we demonstrate that this analysis lacks sufficient accuracy when studying modes with $$\ell \le n$$ , where $$\ell $$ is the multipole number and $\textit{n}$ is the overtone number. To address this, we compute the quasinormal frequencies using the precise Leaver method. Our results show that while the fundamental mode deviates only slightly from the Schwarzschild value, the first few overtones exhibit significantly larger deviations, with the discrepancy growing rapidly with the overtone number. Moreover, beginning with the second overtone, we observe a striking phenomenon: the real part of the frequency tends to zero quickly as the non-minimal coupling constant increases. This combination of spectral stability in the fundamental mode and high sensitivity of the overtones suggests that the Yang–Mills contribution primarily deforms the metric in the near-horizon region, while the geometry quickly transitions back to a Schwarzschild-like form at larger radii. In addition, we compute the grey-body factors and confirm that they represent a more stable characteristic of the geometry, exhibiting a correspondence with quasinormal modes already at the first multipole. The Yang–Mills coupling enhances the grey-body factors, further increasing the transmission probability.

Czechia

B. Lütfüoğlu

Non-minimal Einstein–Yang–Mills black holes: fundamental quasinormal mode and grey-body factors versus outburst of overtones

Using the AdS/CFT correspondence, we investigate the holographic image of an AdS black hole in Einstein-power-Yang-Mills gravity. The AdS boundary hosts a Gaussian oscillation source, which induces a lensed response on the opposite side of the boundary during propagation through bulk spacetime. The optical system enables observers at the north pole to continuously capture holographic images that exhibit an axisymmetric bright ring known as the Einstein ring. As the observation position shifts, the bright ring gradually transforms into a luminous arc and eventually transitions into a light point. Additionally, we examine the impact of variations in relevant physical quantities on the ring and present the corresponding brightness curve. The results indicate that, as the temperature $\textit{T}$ and nonlinear Yang Mills charge parameter $\textit{q}$ increase, the ring radius increases, whereas an increase in chemical potential $\textit{u}$ leads to a decrease in ring radius. However, the peak brightness curve of the ring invariably decreases as the values of $\textit{T}$, $\textit{u}$, and $\textit{q}$ increase, albeit to varying degrees. Comparing the outcomes of geometric optics, we observe that the position of the ring in holography images is consistent with that of the photon ring.

Xin-Yun Hu

Ke-Jian He

Xiao-Xiong Zeng

Holographic image features of an AdS black hole in Einstein-power-Yang-Mills gravity * Supported by the National Natural Science Foundation (11875095), the Innovation and Development Joint Foundation of Chongqing Natural Science Foundation (CSTB2022NSCQ-LZX0021), the Basic Research Project of Science and Technology Committee of Chongqing, China (CSTB2023NSCQ-MSX0324), and the Natural Science Foundation of Chongqing, China (CSTB2023NSCQ-MSX0594)

The production of heavy-quark (HQ) jets is a new area that addresses the mass effect of jet quenching in heavy-ion physics. This paper presents a theoretical study of HQ jet yield suppression in Pb+Pb collisions at the Large Hadron Collider (LHC) and focuses on the energy loss of HQ jets produced by different mechanisms. The $\textit{p+p}$ baseline is provided by the generator simulation of high-energy reactions of particles (SHERPA), and the jet-medium interactions are described by the SHELL transport model, which considers the elastic and inelastic partonic energy loss in the quark-gluon plasma (QGP). In $\textit{p+p}$ collisions, our numerical results indicate that the HQ jets from gluon splitting ( $ g \rightarrow Q $ -jet) are the dominant contribution at high $ p_T $ , displaying more dispersive structures than the HQ-initiated ( $ Q \rightarrow Q $ -jet). In nucleus-nucleus collisions, our calculations were consistent with the inclusive and b-jet $ R_{AA} $ recently measured by the ATLAS collaboration, revealing a remarkable manifestation of the mass effect of jet energy loss. As a result of the dispersive substructure, the $ g \rightarrow Q $ -jet loses more energy than the $ Q \rightarrow Q $ -jet in the QGP. Due to the significant contribution of $ g \rightarrow c $ -jet, the $ R_{AA} $ of $\textit{c}$-jet is comparable or even smaller than that of inclusive jet. To experimentally distinguish the $ g \rightarrow Q $ -jet and $ Q \rightarrow Q $ -jet, we propose event selection strategies based on their topological features and test their performances. By isolating the $ c \rightarrow c $ -jet, $ b \rightarrow b $ -jet, and the jets initiated by heavy quarks, we predicted that the order of their $ R_{AA} $ are in line with the mass hierarchy of energy loss. Future measurements on the $ R_{AA} $ of $ Q \rightarrow Q $ -jet and $ g \rightarrow Q $ -jet will provide a unique opportunity for testing the flavor/mass dependence of energy loss at the jet level.

Sa Wang

Shuang Li

Yao Li

Ben-Wei Zhang

Enke Wang

Probing the mass effect of heavy quark jets in high-energy nuclear collisions * Supported by the MajorProject of Basic and Applied Basic Research of Guangdong Province, China (2020B0301030008, 2023A1515011460), and the National Natural Science Foundation of China (11935007, 12035007, 12247127, 12375137). Sa Wang is supported by the Open Foundation of Key Laboratory of Quark and Lepton Physics (MOE) (QLPL2023P01) and the Talent Scientific Star-up Foundation of the China Three Gorges University, China (CTGU) (2024RCKJ013)

<p>In this work, we investigated the off-shell expansion relation of the Yang-Mills scalar theory. We explicitly showed that the single-trace Berends-Giele currents in the Yang-Mills scalar theory can be decomposed into a term expressed by a linear combination of bi-adjoint scalar Berends-Giele currents and one that vanishes under the on-shell limit. We proved that the bi-adjoint scalar currents, as well as the corresponding coefficients, can be characterized by a graphic approach that was originally studied in the Einstein-Yang-Mills expansion. Furthermore, we generalized the decomposition to the multitrace case through unifying relations and established the connection both in single-trace and multitrace graphic descriptions. Finally, we established the relations between the Yang-Mills currents and the single-trace Yang-Mills scalar currents, choosing special reference orders of the Yang-Mills graphs.</p>

Yi-Xiao Tao

Germany

Konglong Wu

Off-shell expansion relation of the Yang-Mills scalar theory

We combine the Yang-Baxter (YB) and bi-Yang-Baxter (bi-YB) deformations with higher-spin auxiliary field deformations to construct multi-parameter families of integrable deformations of the principal chiral model on a Lie group $\textit{G}$ with semi-simple Lie algebra $$ \mathfrak{g} $$ . In the YB case, our construction produces one integrable deformation for each pair ( $$ \mathcal{R} $$ $\textit{, E}$), where $$ \mathcal{R} $$ is an antisymmetric bilinear operator on $$ \mathfrak{g} $$ obeying the modified classical Yang-Baxter equation and $\textit{E}$ is a function of several variables. In the bi-YB case, the pair becomes a triplet ( $$ \mathcal{R} $$ $\textit{,}$ $$ \overset{\sim }{\mathcal{R}} $$ $\textit{, E}$), where $$ \overset{\sim }{\mathcal{R}} $$ is another antisymmetric bilinear operator on $$ \mathfrak{g} $$ obeying the modified classical Yang-Baxter equation. We show that every model in these families is (weakly) classically integrable by exhibiting a Lax representation for their equations of motion.

Thailand

Daniele Bielli

Christian Ferko

Australia

Liam Smith

Gabriele Tartaglino-Mazzucchelli

Auxiliary field sigma models and Yang-Baxter deformations

We construct invertible spectral parameter dependent Yang-Baxter solutions ($\textit{R}$-matrices) by Baxterizing constant non-invertible Yang-Baxter solutions. The solutions are algebraic (representation independent). They are constructed using supersymmetry (SUSY) algebras. The resulting $\textit{R}$-matrices are regular leading to local non-hermitian Hamiltonians written in terms of the SUSY generators. As particular examples we Baxterize the 4 × 4 constant non-invertible solutions of Hietarinta leading to nearest-neighbor Hamiltonians. On comparing with the literature we find that two of the models are new. Apart from being non-hermitian, many of them are also non-diagonalizable with interesting spectrums. With appropriate representations of the SUSY generators we obtain spin chains in all local Hilbert space dimensions.

India

Somnath Maity

Pramod Padmanabhan

Vladimir Korepin

Non-hermitian integrable systems from constant non-invertible solutions of the Yang-Baxter equation

We study $$ \mathcal{N} $$ = 1 SU($\textit{N}$) super Yang-Mills (SYM) theory on $\textit{ℝ}$ × ($\textit{S}$ ) × ($\textit{S}$ ) with the ’t Hooft twist. The theory becomes weakly coupled if the length $\textit{L}$ of ($\textit{S}$ ) is sufficiently small, $\textit{NL}$ Λ ≪ 1. We explore the nonperturbative dynamics at the weak-coupling regime by changing the size of $\textit{L}$ and uncover how 3d monopole/bion-based effective theory for $\textit{L}$ ≫ $\textit{L}$ is related to the 2d vortex-based theory for $\textit{L}$ ≈ $\textit{L}$ . The highlights of our results are (1) the smooth “weak-weak” continuity of the vacuum structure and gluino condensate during the 3d-2d dimensional reduction, (2) the switching of Wilson loop behavior from the area law in 3d to the perimeter law in 2d via a “double-string” picture, (3) the role of mass deformation in breaking discrete chiral symmetry and restoring the area law in 2d, and (4) the microscopic investigation of bions during the reduction from 3d to 2d and the cancellation of the vacuum energy due to the hidden topological angle. We also discuss the generalization of our results for (1)–(3) from $$ \mathcal{N} $$ = 1 SYM to QCD with adjoint quarks.

Japan

Yui Hayashi

Tatsuhiro Misumi

Yuya Tanizaki

Monopole-vortex continuity of $$ \mathcal{N} $$ = 1 super Yang-Mills theory on $\textit{ℝ}$