Schedule

Seok Kim

Title : Hairy AdS black holes

Abstract : I will explain the recent constructions of hairy AdS black holes and suggest resolutions of some puzzles on these objects in the past. For supersymmetric hairy black holes, we quantitatively test their existence from the dual SCFT.

Siyul Lee

Title : D2-brane holography and black holes

Abstract : The Dp-brane holography generalizes the AdS/CFT correspondence by building on D-branes with dimensions other than 3. Despite difficulties coming from lack of AdS vacua and conformal symmetry, modern techniques such as supersymmetric localization make precision holography possible. In this talk, I will review the holography of spherical D-branes and present a Schwarzschild-like black hole in D2-brane holography.

Wenbin Yan

Title : Chiral algebra, Wilson lines, and mixed Hodge structure of Coulomb branch

Abstract : In the talk we will discuss an intriguing relation between the chiral algebra and the mixed Hodge structure of the Coulomb branch of four dimensional N = 2 superconformal field theories. Using Wilson line operators and modularity, one can compute characters of modules of VOAs corresponding to class-S theories. One can then check that the representation information is also encoded into the pure part of the mixed Hodge structure of the Coulomb branch of the same theory. This provides more relation between the Higgs and Coulomb branch of 4d N=2 theories, expanding the scope of 4d mirror symmetry.

Sung-Soo Kim

Title : New perspective on S-folds of 5d SCFTs

Abstract : We present a novel viewpoint on S-folds of 5d superconformal field theories (SCFTs), constructed as discrete Z_n quotients of 5-brane webs in Type IIB string theory. These S-fold constructions yield new classes of SCFTs that lack gauge theory deformations, enriching the landscape of five-dimensional quantum field theories. Focusing on the illustrative case of Z_2 S-folds, we analyze some physical observables and, in particular, construct the associated Seiberg-Witten curves. Our results reveal intriguing connections between the properties of these S-folds and recent developments in the understanding of orientifold planes, offering deeper insight into the role of discrete symmetries in 5d SCFTs.

Matteo Sacchi

Title : A 2d/2d unitary/non-unitary correspondence, Part I

Abstract : We introduce a correspondence relating the S^2 partition functions of certain 2d N=(2,2) theories to correlators of non-unitary 2d CFTs. Similarly to AGT, we begin with a 4d N=2 SCFT on S^2 x Sigma, with Sigma a punctured Riemann surface: a topologically twisted reduction on Sigma yields the (2,2) theory on S^2, while reducing on S^2 produces the CFT on Sigma. The chiral algebra of the resulting CFT is equal to the VOA of the parent 4d SCFT, thereby extending the SCFT/VOA correspondence to a full CFT.  We outline the framework and illustrate it with free theories and Argyres-Douglas SCFTs related to minimal models.

Gabi Zafrir

Title : A 2d/2d unitary/non-unitary correspondence, Part II

Abstract : Dimensional reduction often implies non-trivial connections between field theories in different dimensions. A well-known example is the AGT (Alday-Gaiotto-Tachikawa) type relation that connects partition functions of different theories sharing a common higher dimensional ancestor. In this talk we shall exploit this relation to study the compactification of the 4d H0 SCFT on Riemann surfaces to get 2d (2,2) theories. Specifically, we shall argue for a 2d/2d unitary/non-unitary correspondence of AGT type between the resulting 2d theories and the Lee-Yang minimal model. We use this to identify the resulting 2d theories for certain choices of the Riemann surfaces, and test them with a variety of consistency checks.

Arash Ardehali

Title : Cardy limit of superconformal indices in d=3,4

Abstract : We review recent progress on Cardy limit of the 4d superconformal index and its connection with supersymmetric gauge dynamics on R^3xS^1. We also present new results on Cardy limit of the 3d superconformal index, highlighting in particular the emergence of punctured surfaces in the problem and their competition with punctures in setting the asymptotics.

Minseok Cho (Short Talk)

Title : Large landscape of 4d superconformal field theories from small gauge theories

Abstract : We systematically explore the broad landscape of RG flows of 4d N=1 SCFTs triggered by relevant deformations including flipping. This talk will present interesting features and examples from this landscape, focusing on the distribution of central charges. I will show how a vast number of fixed points can emerge from just a few small seed gauge theories. This approach uncovers new patterns and phenomena, such as dualities and a new maximal a/c theory.

Heesu Kang (Short Talk)

Title : Non-hyperbolic 3-manifolds and 3D field theories for 2D minimal model RCFTs

Abstract : In this talk, I present a concrete 3D realization of two-dimensional rational chiral algebra by engineering quantum field theories on non-hyperbolic 3-manifolds via the 3D–3D correspondence. I construct explicit bulk theories for the Virasoro, N=1 super-Virasoro, and W_N minimal models, and reproduce their modular data from these bulk theories. A unified framework for constructing the bulk field theory from T[SU(n)] building blocks will also be presented. The picture indicates a sharp IR dichotomy—unitary RCFTs correspond to gapped 3D TQFTs, whereas non-unitary cases arise from topologically twisted rank-0 N=4 SCFTs.

Shlomo Razamat

Title : Generalized Schur partition functions and RG flows

Abstract : We revisit a double-scaled limit of the superconformal index of ${\cal N}=2$ superconformal field theories (SCFTs) which generalizes the Schur index. The resulting partition function, $\hat {\cal Z}(q,\alpha)$, has a standard $q$-expansion with coefficients depending on a continuous parameter $\alpha$. The Schur index is a special case with $\alpha=1$. Through explicit computations we argue that this partition function is an invariant of certain mass deformations and vacuum expectation value (vev) deformations of the SCFT. In particular, two SCFTs residing in different corners of the same Coulomb branch, satisfying certain restrictive conditions, have the same partition function with a non-trivial map of the parameters, $\hat {\cal Z}_1(q,\alpha_1)=\hat {\cal Z}_2(q,\alpha_2(\alpha_1))$. For example, we show that the Schur index of all the SCFTs in the Deligne-Cvitanovi\'c series is given by special values of $\alpha$ of the partition function of the $SU(2)$ $N_f=4$ ${\cal N}=2$ SQCD.

Kihong Lee

Title : Large N SCFTs in 4d and Universality

Abstract : I will talk about 4d SCFTs that appear as IR fixed points of the supersymmetric gauge theories with simple gauge groups which admit large N limits. We find the theories are classified in 3(+1) classes by their matter contents. I will then discuss universal behaviors within and across classes.

Chi-Ming Chang

Title : Introduction to Supercharge Q-cohomology and Fortuity Phenomenon

Abstract : I will introduce the supercharge Q-cohomology in holographic quantum field theories, and a classification of cohomology classes into monotone and fortuitous. I will discuss the holographic interpretation of the classification, focusing on N=4 SYM. Finally, I will discuss the behavior of the classical Q-cohomology under S-duality, and the potential quantum corrections to the cohomology.

Sunjin Choi

Title : Holography on ADE singularities

Abstract : I will talk about basic aspects of the AdS/CFT correspondence of four-dimensional N=4 U(N) super Yang-Mills theory when it is put on S3/\Gamma, where \Gamma is an arbitrary finite subgroup of SU(2). After giving a field-theoretical derivation that there is a huge vacuum degeneracy due to the choice of gauge holonomy, I will describe in detail a chain of string dualities, which maps this vacuum degeneracy to that of three-dimensional level-N Chern-Simons theory whose gauge group is determined by \Gamma. I will also briefly comment on how the S-duality and the one-form symmetry act in this duality.