Program

March 27 (Wed)

10:00 - 11:00
Jaewon Song "Universality of Superconformal Index, Holography and Information Paradox"  slides


11:30 – 12:30
Satoshi Nawata "Class S on S^2"  slides
Abstract: In my talk, I will delve into the 2d N=(0,2) and N=(0,4) theories, derived from class S theories compactified on S^2 with a topological twist. My presentation will focus on elucidating the TQFT structure on Riemann surfaces. Furthermore, I will discuss the connection between the left-moving sector of the (0,2) theory and the chiral algebra of the 4d N=2 theory. Specifically, I propose that the (0,2) elliptic genus of a theory in this class can be expressed as a linear combination of characters from the chiral algebra. This talk is based on a collaboration with Yiwen Pan and Jiahao Zheng [arXiv:2310.07965].

14:30 – 15:30
Dongmin Gang "3D N=4 rank-0  SCFTs, non-unitary TQFTs and rational VOAs"  slides
Abstract: I will talk about a non-unitary version of bulk-boundary correspondence, which relates  2D chiral rational CFTs to topologically twisted 3D N=4 rank-0 SCFTs.

16:00 – 17:00
Junya Yagi “Tetrahedron equation and trialities of 2D supersymmetric gauge theories”  slides

Abstract: Recently, connections have been discovered between supersymmetric gauge theories and the Zamolodchikov tetrahedron equation which is a 3D analog of the Yang-Baxter equation. I will present two solutions of the tetrahedron equation, related to the trialities of 2D N = (0,2) quiver gauge theories with U(N) gauge groups and N = (0,1) quiver gauge groups with SO(2N) gauge groups.

March 28 (Thu)

10:00 - 11:00
Mathew Buican  "A New Symmetry for 4d N=2 SCFTs"
Abstract: I will describe some ongoing work on identifying and constructing a new symmetry for large classes of 4d N=2 SCFTs.

11:30 – 12:30
Yuya Tanizaki "Wilson-'t Hooft classifications and N=4 SYM gapped vacua in view of 1-form symmetry"  slides
Abstract: Since late 70's we have classified the gapped vacua of 4d Yang-Mills theory with adjoint matters by studying the area vs perimeter law of Wilson and 't Hooft loops, and this Wilson-'t Hooft classification plays an important role for our understanding of color confinement. Its original derivation, however, has subtlety related to the fact that magnetic (or dyonic) loops are not genuine line operators, and it is important to revisit this classification problem from the modern view of 1-form symmetry. We prove the 1-to-1 correspondence between the original Wilson-'t Hooft classification and the spontaneous breaking of 1-form symmetry stacked with the SPT states of unbroken symmetry, and examine it for the gapped vacua of N=4 supersymmetric Yang-Mills theory. 

14:30 – 15:30
Kantaro Ohmori "Topological terms in sigma models, simplicial model of equivariant cohomology, and anomaly"
Abstract: For a Lagrangian to exhibit symmetry, preservation up to a surface term is sufficient. This surface term modifies the Noether current and, consequently, the charge operator. Additionally, it is possible to identify "higher surface terms" that modify the Lagrangian at junctions of symmetry operators, which are exponentiations of charge operators in the context of a continuous group. We will demonstrate how these higher surface terms closely align with a simplicial model of equivariant (differential) cohomology. Our framework provides an explicit understanding of the fact that the transgression class, obstructing the equivariant uplift, characterizes the 't Hooft anomaly. This correspondence between the anomaly and the transgression class was highlighted by Witten in 1991 and further detailed by Freed in 2006 for the case of WZW models.

16:00 – 17:00
Saghar Sophie Hosseini “Symmetry topological field theories from edge modes”

Abstract: (D+1)-dimensional symmetry topological field theories, known as SymTFTs, contain information about choices of generalised global symmetries and anomalies of D-dimensional QFTs. In the case of geometrically engineered QFTs, SymTFTs are argued to emerge through the reduction of the 10-dimensional topological effective action in string theory. In this talk, I will give an introduction to SymTFTs and discuss a different viewpoint where they arise from 11-dimensional topological actions, realising the string theory fields as edge modes, thereby addressing certain previously known subtleties.


17:15 - 18:15
Kazuya Yonekura “Dualities among Neveu-Schwarz sector branes in string theory”  slides

Abstract: We conjecture dualities among branes that consist of Neveu-Schwarz sector fields, such as NS5-branes. Two branes are dual after compactifications on spheres with gauge fluxes. The conjecture follows from simple considerations on string worldsheet theories. For some NS5-branes, we get level-rank dualities of Chern-Simons theories. Application of the dualities to a newly found brane in heterotic string theory reveals surprising properties of the worldvolume theory on it.

March 29 (Fri)

10:00 - 11:00
Kohki Kawabata "Supersymmetric conformal field theories from quantum stabilizer codes"
Abstract: We construct fermionic conformal field theories (CFTs) whose spectra are characterized by quantum stabilizer codes. We exploit our construction to search for fermionic CFTs with supersymmetry by focusing on quantum stabilizer codes of the Calderbank-Shor-Steane type, and derive simple criteria for the theories to be supersymmetric. We provide several examples of fermionic CFTs that meet the criteria, and find quantum codes that realize N=4 supersymmetry. Our work constitutes a new application of quantum codes and paves the way for the methodical search for supersymmetric CFTs.

11:30 – 12:30
Yuma Furuta "On the discrete torsions of simple current orbifold of Narain CFT and its meaning in the code theory"  slides
Abstract: We consider an orbifold of a kind of CFT called Narain CFT. The orbifold under consideration this presentation is a special type known as a simple current orbifold, which is characterized by symmetries formed by special primary fields. There exist degrees of freedom when performing twists, classified by the cohomology of certain groups known as discrete torsion. We explore the physical significance of this simple current orbifold in Narain CFT and ultimately provide its code theory interpretation.

14:30 – 15:30
Yutaka Yoshida "Quantized Coulomb branch  of 4d $\mathcal{N}=2$  $SU(2)$ gauge theory and $C^{\vee} C_{1}$ spherical DAHA"
Abstract: We study the algebra of BPS Wilson, 't Hooft, and Dyonic loop operators in 4d $\mathcal{N}=2$ $SU(2) \simeq Sp(1)$ gauge theory with four fundamental hypermultiplets. We find that the deformation quantization of the SUSY localization formula for loop operators agrees with the polynomial representation of the spherical part of the double affine Hecke algebra (spherical DAHA) of $C^{\vee} C_1$-type. We conjecture that the quantized $K$-theoretic Coulomb branch of $Sp(N)$ gauge theory with four hypermultiplets in the vector representation and a hypermultiplet in the anti-symmetric representation is isomorphic to the spherical DAHA of $C^{\vee} C_N$-type.

16:00 – 17:00
Hiroshi Itoyama "Critical Phenomena around AD Singularities by Matrices"  slides
Abstract: the contents of my talk are

1)a quick derivation of PII from the Nf=2, su(2)  by the double scaling limit

2)large order behavior near the AD point 

3)critical hypersurfaces by the principle of maximal symmetry leading to  flavor mass relations: An-1 quiver matrix model

4)a few scattered results & observations