| Program | Home > Program |
Oct. 24 (Mon)
Hori (Kavli IPMU) "2d Seiberg duality, with boundary"
N. Kim (Kyunghee) "Precision tests of AdS/CFT and Matrix Models"
Closset (CERN) "A-twist and dualities in two and three dimensions"
I will review recent localization results for supersymmetric correlation functions of A-twisted two-dimensional N=(2,2) gauge theories on Riemann surfaces. Using these results, I will provide some interesting checks of infrared dualities for various gauge groups. I will also briefly explain how these localisation results naturally uplift to three-dimensional N=2 theories on a large family of three-manifolds, including the three-sphere.
H. Kim (Perimeter Institute) "Supersymmetric Indices of 3d TQFTs on a Riemann surface"
I will discuss the partition function of three-dimensional supersymmetric topological field theories defined on a circle bundle over Riemann surface and correlation functions of half-BPS loop operators. From the result, I will derive the quantum algebra of Wilson loops in terms of the associated Bethe equation, and show how the Seiberg-like dualities act on the half-BPS Wilson loops.
Huang (USTC, Hefei) "Elliptifying Topological String Theory"
Building on our previous work arXiv:1501.04891, we provide some more studies of topological strings on compact elliptic Calabi-Yau spaces.
J. Park (Sogang) "Doubled-yet-gauged"
Ever since Einstein introduced Riemannian geometry to physics literature -- to formulate his theory of gravity -- the Riemannian metric has been privileged to be the only geometric and gravitational field. Yet, string theory suggests to view the whole massless NS-NS sector as the gravitational unity. Recently, under the name of Double Field Theory, this idea has been concretely realized. I will review both target spacetime as well as world-sheet aspects.
Oct. 25 (Tue)
Plesser (Duke U)
Jockers (Bonn) "2d non-Abelian GLSM correlators & quantum cohomology"
In this talk I review the correspondence between 2d GLSM correlators and quantum cohomology ring in non-linear sigma model phases. Focussing on certain non-Abelian GLSM models, I argue that for CY 3-fold and CY 4-fold non-linear sigma model target space geometries the discussed correlators respectively exhibit certain quantum-corrected cohomology relations and the intricate CY 4-fold quantum cohomology ring. This talk is based upon work with Andreas
Gerhardus and work in progress with Andreas Gerhardus and Urmi Ninad.
In this talk I review the correspondence between 2d GLSM correlators and quantum cohomology ring in non-linear sigma model phases. Focussing on certain non-Abelian GLSM models, I argue that for CY 3-fold and CY 4-fold non-linear sigma model target space geometries the discussed correlators respectively exhibit certain quantum-corrected cohomology relations and the intricate CY 4-fold quantum cohomology ring. This talk is based upon work with Andreas
Gerhardus and work in progress with Andreas Gerhardus and Urmi Ninad.
B.Kim (KIAS) "Quasimap Wall-crossings"
My talk will be based on a joint work with I. Ciocan-Fontanine. I will introduce a wall-crossing formula for the virtual classes of epsilon-stable quasimaps to GIT quotients and sketch its proof for complete intersections in projective space, with no positivity restrictions on their first Chern class. As a consequence, the wall-crossing formula relating the genus g descendant Gromov-Witten potential and the genus g epsilon-quasimap descendant potential is established. For the quintic threefold, the results may be interpreted as giving a rigorous and geometric interpretation of the holomorphic limit of the BCOV B-model partition function of the mirror family.
S.-J. Lee (Virgina Tech) "Multiple Fibrations in Calabi-Yau Geometry and String Dualities"
We study the ubiquity of multiple fibration structures in known constructions of Calabi-Yau manifolds and explore the role they play for string dualities. Upon introducing new tools for resolved Calabi-Yau varieties, we analyze a set of F-theory effective theories associated to the different elliptic fibrations and relate them via the M-/F-theory correspondence. Explicit geometric examples will include higher-rank Mordell-Weil groups and non-flat fibrations. In addition, in the context of heterotic/F-theory duality, we also investigate the role played by multiple nested structures of K3- and elliptic fibrations in known and novel string dualities in various dimensions.
Tomasiello (Milano) "Fivebranes and T-branes"
I will review some recent results regarding the dynamics of M5-branes at singularities. In the case of a Z_k singularity, one can Higgs the theory to produce massive IIA configurations whose AdS7 duals are explicitly known. Some of their compactifications on Riemann surfaces with and without punctures produce new AdS5 solutions with many intersecting sources. For D_k and E_k singularities, F-theory reveals a rich web of 6d conformal theories largely inaccessible to perturbative strings.
I will review some recent results regarding the dynamics of M5-branes at singularities. In the case of a Z_k singularity, one can Higgs the theory to produce massive IIA configurations whose AdS7 duals are explicitly known. Some of their compactifications on Riemann surfaces with and without punctures produce new AdS5 solutions with many intersecting sources. For D_k and E_k singularities, F-theory reveals a rich web of 6d conformal theories largely inaccessible to perturbative strings.
Oct. 26 (Wed)
S. Lee (KIAS)
Putrov (IAS, Princeton) "BPS spectra of 3-manifolds "
In my talk I will show how one can obtain integer-valued invariants from CS partition function on closed 3-manifold. Physically these numbers can be interpreted as counting of M2-branes ending on 3-manifold and can be categorified, similarly to the way Khovanov homology categorifies Jones polynomial of a knot. I will discuss interpretation in terms of resurgence theory and relation to DT/GW correspondence in topological strings.
Lazaroiu (CGP, Pohang) “Generalized Einstein-Scalar-Maxwell theories and locally geometric U-folds”
I describe a generalization of Einstein-Scalar-Maxwell theories which affords a global geometric interpretation of certain locally geometric U-folds and makes possible a wide class of globally inequivalent formulations of supergravity theories which are however locally equivalent with the traditional description. The formulation uses a twist of the Abelian gauge theory coupled to gravity and scalar matter. I also mention briefly a further generalization which promises a geometric description of the classical limit of the most general U-fold backgrounds.
Prins (Lyon) "Mirror symmetry, supersymmetry and generalized geometry on $SU(4)$-structure vacua"
Recently, there has been some progress in examining mirror symmetry beyond Calabi-Yau threefolds. I will discuss how this is related to flux vacua of type II supergravity on eight-dimensional manifolds equipped with SU(4)-structure. It will be shown that the natural framework to describe such vacua is generalized complex geometry. Two classes of type IIB solutions will be given, one of which is complex, the other symplectic, and I will describe in what sense these are mirror to one another.
Morrison (UC Santa Barbara) “Recent progress in G2 compactifications”
There has been recent mathematical progress in the construction of manifolds with holonomy G2, using algebraic geometry to construct an approximate G2 manifold, and then using geometric analysis to construct an appropriate metric on the space. This progress opens the door to the exploration of four-dimensional physical theories obtained by compactifying M-theory on such manifolds. Realistic M-theory models require singularities in the compactifying space, and we will discuss how the construction methods need to be modified to accommodate this. Based on joint work with Jim Halverson, and on work in progress.