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1. Flowing to $$ \mathcal{N} $$ = 3 Chern-Simons-matter theory

   https://doi.org/10.1007/JHEP03(2020)100  

   Guarino, Adolfo; Tarrío, Javier; Varela, Oscar (March 2020, Journal of High Energy Physics)

   null (Ed.)

   A bstract New renormalisation group flows of three-dimensional Chern-Simons theories with a single gauge group SU( N ) and adjoint matter are found holographically. These RG flows have an infrared fixed point given by a CFT with $$ \mathcal{N} $$ N = 3 supersymmetry and SU(2) flavour symmetry. The ultraviolet fixed point is again described by a CFT with either $$ \mathcal{N} $$ N = 2 and SU(3) symmetry or $$ \mathcal{N} $$ N = 1 and G 2 symmetry. The gauge/gravity duals of these RG flows are constructed as domain-wall solutions of a gauged supergravity model in four dimensions that enjoys an embedding into massive IIA supergravity. A concrete RG flow that brings a mass deformation of the $$ \mathcal{N} $$ N = 2 CFT into the $$ \mathcal{N} $$ N = 3 CFT at low energies is described in detail. 

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2. 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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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. Charmless B → PPP decays: The fully antisymmetric final state

   https://doi.org/10.1103/PhysRevD.109.013001  

   Bhattacharya, Bhubanjyoti; Fines-Neuschild, Mirjam; Houck, Andrea; Imbeault, Maxime; Jean, Alexandre; London, David (January 2024, Physical Review D)

   Under flavor SU(3) symmetry (SU(3)_F), the final-state particles in B → PPP decays (P is a pseudoscalar meson) are treated as identical, and the PPP must be in a fully-symmetric(FS) state, a fully-antisymmetric (FA) state, or in one of four mixed states. In this paper, we present the formalism for the FA states. We write the amplitudes for the 22 B → PPP decays that can be in an FA state in terms of both the SU(3)_F reduced matrix elements and diagrams. This shows the equivalence of diagrams and SU(3)_F. We also give 15 relations among the amplitudes in the SU(3)_F limit as well as the additional four that appear when the diagrams E/A/PA are neglected. We present sets of B → PPP decays that can be used to extract γ using the FA amplitudes. The value(s) of γ found in this way can be compared with the value(s) found using the FS states. 

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5. Electroweak flavour unification

   https://doi.org/10.1007/JHEP09(2022)193  

   Davighi, Joe; Tooby-Smith, Joseph (September 2022, Journal of High Energy Physics)

   A bstract We propose that the electroweak and flavour quantum numbers of the Standard Model (SM) could be unified at high energies in an SU(4) × Sp(6) L × Sp(6) R anomaly-free gauge model. All the SM fermions are packaged into two fundamental fields, Ψ L ∼ ( 4 , 6 , 1 ) and Ψ R ∼ ( 4 , 1 , 6 ), thereby explaining the origin of three families of fermions. The SM Higgs, being electroweakly charged, necessarily becomes charged also under flavour when embedded in the UV model. It is therefore natural for its vacuum expectation value to couple only to the third family. The other components of the UV Higgs fields are presumed heavy. Extra scalars are needed to break this symmetry down to the SM, which can proceed via ‘flavour-deconstructed’ gauge groups; for instance, we propose a pattern Sp(6) L → $$ {\prod}_{i=1}^3\mathrm{SU}{(2)}_{L,i}\to \mathrm{SU}{(2)}_L $$ ∏ i = 1 3 SU 2 L , i → SU 2 L for the left-handed factor. When the heavy Higgs components are integrated out, realistic quark Yukawa couplings with in-built hierarchies are naturally generated without any further ingredients, if we assume the various symmetry breaking scalars condense at different scales. The CKM matrix that we compute is not a generic unitary matrix, but it can precisely fit the observed values. 

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