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1. Generalized symmetry enriched criticality in (3+1)d

   https://doi.org/10.21468/SciPostPhys.19.6.145  

   Moy, Benjamin (January 2025, SciPost Physics)

   We construct two classes of continuous phase transitions in 3+1 dimensions between gapped phases that break distinct generalized global symmetries. Our analysis focuses onSU(N)/\mathbb{Z}_N $SU\left(N\right)/{\mathbb{Z}}_N$ gauge theory coupled toN_f $N_f$ flavors of Majorana fermions in the adjoint representation. ForN $N$ even and sufficiently large oddN_f $N_f$ , upon imposing time-reversal symmetry and anSO(N_f) $SO\left(N_f\right)$ flavor symmetry, the massless theory realizes a quantum critical point between a gapped phase in which a\mathbb{Z}_N ${\mathbb{Z}}_N$ one-form symmetry is completely broken and a phase where it is broken to\mathbb{Z}_2 ${\mathbb{Z}}_2$ , leading to\mathbb{Z}_{N/2} ${\mathbb{Z}}_{N/2}$ topological order. We characterize the possible patterns of symmetry fractionalization in these phases and provide an explicit lattice model that exhibits the transition. The critical point has an enhanced symmetry, which includes non-invertible analogues of time-reversal symmetry. Enforcing a non-invertible time-reversal symmetry and theSO(N_f) $SO\left(N_f\right)$ flavor symmetry, forN $N$ andN_f $N_f$ both odd, we demonstrate that this critical point can appear between a topologically ordered phase and a phase that spontaneously breaks the non-invertible time-reversal symmetry, furnishing an analogue of deconfined quantum criticality for generalized symmetries. 

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2. Dynamical up-quark mass generation in QCD-like theories

   https://doi.org/10.1103/38sb-dm8l  

   Csáki, Csaba; Roy, Tuhin S; Ruhdorfer, Maximilian; Youn, Taewook (July 2026, Physical Review D)

   We calculate the dynamically generated up-quark mass in some QCD-like theories with $F=3$ light flavors, obtained from supersymmetric QCD perturbed via anomaly mediated supersymmetry breaking. We match the low-energy effective theory to the traditional chiral Lagrangian of QCD and determine the coefficients to next-to-leading order in chiral perturbation theory, while also varying the number of colors $N$ . We find that the dynamically generated up-quark mass vanishes in the large $N$ limit and is small for $F<N$ ; however, for $F=N$ there is a sizable $\mathcal{O}\left(1\right)$ contribution. While our results are reliable only for small supersymmetry breaking, we observe that extrapolating the $F=N$ result to large supersymmetry breaking would lead to a dynamical up-quark mass that is large enough to account for its entire physical mass. 

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3. Anomalies in hadronic $B$ decays: An update

   https://doi.org/10.1103/5jp1-7cfw  

   Bhattacharya, Bhubanjyoti; Bouchard, Marianne; Hudy, Luke; Jean, Alexandre; London, David; MacKenzie, Christopher (September 2025, Physical Review D)

   Recently, $B\to PP$ decays ( $B=\{B^0,B^{+},B_s^0\}$ , $P=\{\pi ,K\}$ ) were analyzed under the assumption of flavor SU(3) symmetry ( ${\mathrm{SU}\left(3\right)}_F$ ). Although the individual fits to $\mathrm{\Delta }S=0$ or $\mathrm{\Delta }S=1$ decays are good, it was found that the combined fit is very poor: there is a $3.6\sigma$ disagreement with the ${\mathrm{SU}\left(3\right)}_F$ limit of the standard model ( ${\mathrm{SM}}_{{\mathrm{SU}\left(3\right)}_F}$ ). One can remove this discrepancy by adding ${\mathrm{SU}\left(3\right)}_F$ -breaking effects, but 1000% ${\mathrm{SU}\left(3\right)}_F$ breaking is required. In this paper, we extend this analysis to include decays in which there is an $\eta$ and/or ${\eta }^{\prime }$ meson in the final state. We now find that the combined fit exhibits a $4.1\sigma$ discrepancy with the ${\mathrm{SM}}_{{\mathrm{SU}\left(3\right)}_F}$ , and 1000% ${\mathrm{SU}\left(3\right)}_F$ -breaking effects are still required to explain the data. These results are rigorous, group-theoretically—no theoretical assumptions have been made. But when one adds some theoretical input motivated by QCD factorization, the discrepancy with the ${\mathrm{SM}}_{{\mathrm{SU}\left(3\right)}_F}$ grows to $4.9\sigma$ . 

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4. Anomalies in Hadronic $B$ Decays

   https://doi.org/10.1103/PhysRevLett.133.211802  

   Berthiaume, Raphaël; Bhattacharya, Bhubanjyoti; Boumris, Rida; Jean, Alexandre; Kumbhakar, Suman; London, David (November 2024, Physical Review Letters)

   In this Letter, we perform fits to $B\to PP$ decays, where $B=\{B^0,B^{+},B_s^0\}$ and the pseudoscalar $P=\{\pi ,K\}$ , under the assumption of flavor SU(3) symmetry [ ${\mathrm{SU}\left(3\right)}_F$ ]. Although the fits to $\mathrm{\Delta }S=0$ or $\mathrm{\Delta }S=1$ decays individually are good, the combined fit is very poor: there is a $3.6\sigma$ disagreement with the ${\mathrm{SU}\left(3\right)}_F$ limit of the standard model ( ${\mathrm{SM}}_{{\mathrm{SU}\left(3\right)}_{\mathrm{F}}}$ ). One can remove this discrepancy by adding ${\mathrm{SU}\left(3\right)}_F$ -breaking effects, but 1000% ${\mathrm{SU}\left(3\right)}_F$ breaking is required. The above results are rigorous, group theoretically—no dynamical assumptions have been made. When one adds an assumption motivated by QCD factorization, the discrepancy with the ${\mathrm{SM}}_{{\mathrm{SU}\left(3\right)}_{\mathrm{F}}}$ grows to $4.4\sigma$ . Published by the American Physical Society2024 

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5. Unnecessary quantum criticality in $SU (3)$ kagome magnets

   https://doi.org/10.21468/SciPostPhys.20.3.082  

   Zhang, Yunchao; Song, Xue-Yang; Senthil, Todadri (January 2026, SciPost Physics)

   Algebraic/Dirac spin liquids (DSLs) are a class of critical quantum ground states that do not have a quasi-particle description. DSLs and related spin liquid phases often arise in strongly frustrated quantum spin systems, in which strong correlations and quantum fluctuations among constituent spins persist down to zero temperature. In this work, we analyze Mott insulating phases ofSU(3) $SU\left(3\right)$ fermions on a kagome lattice which may realize a DSL phase, described at low energies by(2 + 1)d $(2+1)d$ quantum electrodynamics (QED_3 ${}_3$ ) withN_f=6 $N_f=6$ Dirac fermions. By analyzing the action of physical symmetries on the operators of the QED_3 ${}_3$ theory, we conclude that the low energy DSL is a quantum critical point that can be accessed by tuning a single microscopic parameter. Aided by the emergent symmetry and anomalies of the low energy effective theory, we conjecture and present supporting arguments that theSU(3) $SU\left(3\right)$ Kagome magnet DSL is an unnecessary quantum critical point, lying completely within a single phase. 

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