arXiv subjects

Shani Nadir Meynet

Publications and source records attributed to Shani Nadir Meynet.

7 recordsLinked to original sources

arXiv2026

Discrete Gauging of 5d $\mathcal{N}=1$ $E_n$ SCFTs

We study the gauging of discrete symmetries of the 5d rank-one $E_n$ SCFTs that fix the Coulomb branch coordinate but act nontrivially on the Higgs branch chiral ring. Using generalized toric polygons and $(p,q)$-brane webs, we identify symmetries of the moduli space that extend to symmetries of the full SCFT. In many cases they are non-anomalous, and we analyze the moduli space of the gauged theories. We realize the resulting Higgs branch quotients as Coulomb branches of wreathed magnetic quivers and compute their Hilbert series; the flavor algebras extracted from moment maps agree with the fixed-point subalgebras of $\mathfrak{e}_n$. We also lift the discrete actions to the Seiberg--Witten geometry and recover the expected restriction on the mass deformations. For $\mathbb{Z}_2$-wreathings that exchange adjacent gauge nodes, we find that the monopole formula requires a flux-dependent sign and propose a corrected prescription. Finally, we conjecture a higher-rank extension and verify it for the rank-two $E_6/\mathbb{Z}_2$ Higgs branch.

hep-th↗

arXiv2026

Higher anomalies, compressing SPTs and cohomology operations

We explicitly compute and tabulate the suspension map for cohomology operations, applying it to the dimensional reduction of anomalies and higher group structures of generalised symmetries in quantum field theories and lattice systems. In a quantum system with a discrete $p$-form symmetry, we can restrict the symmetry defects to a codimension-$q$ subspace of spacetime, or equivalently confine the gauge field to a slab whose thickness approaches zero. This results in a $(p-q)$-form symmetry on the subspace. We determine the fate of two important properties of symmetries under this process. First, we compute the anomaly of the reduced symmetry, or the higher anomaly of the original symmetry, which acts as an obstruction to higher gauging and onsiteability. Second, for two symmetries forming a higher-group structure, encoded as a Postnikov class, we compute the reduced higher-group structure, which may or may not be trivial. Both cases are captured by the $q$-fold iteration of the cohomology suspension $Ω$, also known as the loop functor or transgression, in the cohomology of Eilenberg--MacLane spaces. Classical results state that $Ω$ is an isomorphism in a stable range and annihilates mixed anomalies. To calculate $Ω$ over a base ring which is not a field, we make use of small models for the chain DGAs of Eilenberg--MacLane spaces, pioneered by Cartan and Moore, whose results we review and extend. The critical added step is the improvement of a mod $p$ chain contraction to the $p$-local integers, obtained via a $p$-adic series. We automate the computations in a software package \texttt{emcm}, and provide extensive tables of the results. Finally, to make contact with explicit cochain formulations of cohomology operations, we demonstrate how to calculate cup products and certain cup-$i$ products in this framework.

hep-th↗

arXiv2025

On the Orbifold origin of Higher Form Symmetries in Geometric Engineering

In this work we explore the relation between orbifold singularities and higher form symmetries. Using the geometric engineering dictionary, we argue that the discrete higher symmetries of 5d SCFTs constructed from M-theory on a non-compact Calabi-Yau threefold can be related to a quantum symmetry of the associated BPS quiver. Through un-orbifolding the quantum symmetry we obtain a new theory without higher form symmetry, providing a notion of ''minimality'' for a theory. This procedure is carried out via algebraic manipulations of the BPS/McKay quiver describing the crepant resolution of the singular geometry. This technique can also be reverted and thus, starting from any ''minimal'' theory, one can orbifold it and generate new theories with the desired higher form symmetries. We test our technology on classes of 5d SCFTs that arise from M-theory geometric engineering on Calabi-Yau threefolds that are non-toric non-complete intersections, which have historically been challenging to tackle.

hep-th↗

arXiv2025

Symmetries Beyond Branes: Geometric Engineering and Isometries

In this work we consider the relation between finite isometries of the internal space and symmetries of the transverse field theory in Geometric Engineering. On top of the established relation between branes wrapping torsional cycles and topological defects, we study other symmetries of the field theory that are not captured by branes wrapped at infinity. Isometries of the engineering geometry have a representations on the field theory, encoded by their non-trivial actions on exceptional and torsional cycles. In this work we describe such action in general terms. As examples, we focus on three classes of geometric engineering spaces: Du Val singularities, toric Calabi-Yau threefolds and $G_2$ manifolds obtained as fibrations of Du Val singularities over $\mathbb S^3$. In the latter case, we check explicitly that M-theory on Calabi-Yau or $G_2$ manifold with finite isometries reproduces correctly the higher group structures and non-invertible symmetries of the transverse field theories.

hep-th↗

arXiv2024

Emergent Non-Invertible Symmetries Bridging UV and IR Phases -- The Adjoint QCD Example

In this letter, we demonstrate how an emergent non-invertible symmetry along a renormalization group (RG) flow reveals connections between microscopic and macroscopic physics. We illustrate this using (3+1)-dimensional Adjoint QCD with two flavors of Weyl fermions as an example. For the $\mathrm{SU}(2)$ case, Córdova and Dumitrescu proposed a non-supersymmetric deformation of the $\mathcal{N}=2$ SYM theory leading to dynamical abelianization, followed by monopole condensation, and resulting in a confining infrared (IR) phase characterized by disjoint copies of the $\mathbb{CP}^1$ sigma model. In this scenario, we point out that the abelianized phase has an emergent non-invertible symmetry, which is matched with the non-invertible symmetry of the IR $\mathbb{CP}^1$ phase, associated to the Hopf solitons. This result illustrate how an emergent non-invertible symmetry can be used to provide a bridge connecting the IR solitons and their properties with the ones of microscopic degrees of freedom in gauge theories with one-form symmetries. Moreover, based on this insight we generalize these results to other gauge theories with any number of colors, and propose a candidate for the UV baryon operator in all these cases.

hep-th↗

arXiv2024

Remarks on Geometric Engineering, Symmetry TFTs and Anomalies

Geometric engineering is a collection of tools developed to establish dictionaries between local singularities in string theory and (supersymmetric) quantum fields. Extended operators and defects, as well as their higher quantum numbers captured by topological symmetries, can be encoded within geometric engineering dictionaries. In this paper we revisit and clarify aspects of these techniques, with special emphasis on 't Hooft anomalies, interpreted from the SymTFT perspective as obstructions to the existence of Neumann boundary conditions. These obstructions to gauging higher symmetries are captured via higher link correlators for the SymTFT on spheres. In this work, we give the geometric engineering counterpart of this construction in terms of higher links of topological membranes. We provide a consistency check in the context of 5D SCFTs with anomalous 1-form symmetries, where we give two independent derivations of the anomaly in terms of higher links, one purely field theoretical and the other purely geometrical. Along the way, we also recover the construction of non-invertible duality defects in 4D $\mathcal N=4$ SYM from a geometric engineering perspective.

hep-th↗

arXiv2022

Higher Symmetries of 5d Orbifold SCFTs

We determine the higher symmetries of 5d SCFTs engineered from M-theory on a $\mathbb{C}^3 / Γ$ background for $Γ$ a finite subgroup of $SU(3)$. This resolves a longstanding question as to how to extract this data when the resulting singularity is non-toric (when $Γ$ is non-abelian) and/or not isolated (when the action of $Γ$ has fixed loci). The BPS states of the theory are encoded in a 1d quiver quantum mechanics gauge theory which determines the possible 1-form and 2-form symmetries. We also show that this same data can also be extracted by a direct computation of the corresponding defect group associated with the orbifold singularity. Both methods agree, and these computations do not rely on the existence of a resolution of the singularity. We also observe that when the geometry faithfully captures the global 0-form symmetry, the abelianization of $Γ$ detects a 2-group structure (when present). As such, this establishes that all of this data is indeed intrinsic to the superconformal fixed point rather than being an emergent property of an IR gauge theory phase.

hep-th↗