M-theory Workshop Titles and Abstracts

Dongsu Bak (Seoul) "Physics of interface geometries"

The physics of Janus related system including Janus black branes and multiple interface black branes will be discussed. We obtain their free energy, correlated interface entropy and Casimir energy via geometric consideration.

David Berman (QMUL) "Solutions in double and exceptional field theory"

We examine wave, monopole and self-dual dyon solutions in double and exceptional field theories. We interpret these solutions in terms of usual supergravity and examine their properties.

Matthew Buican (Rutgers) "Conformal Manifolds of 4d N=2 SCFTs With Non-Integer Dimension Chiral Primaries"

I will describe new S-dualities found by marginally gauging different global symmetry subgroups of two copies of a certain rank-one Argyres-Douglas theory (along with a number of hypermultiplets) and studying the resulting conformal manifolds. Time permitting, I will then discuss some more exotic phenomena that occur on the conformal manifolds of certain more obscure theories.

Nadav Drukker (KCL) “3d mirror symmetry as a canonical transformation”

The partition function on S^3 of supersymmetric field theories can be reduced via localization to a matrix model. Equivalent theories under some duality, like mirror symmetry, should have the same partition function. This was indeed verified in many examples, usually by employing increasingly complex integral identities. In my talk I will point out that for certain theories which admit a free Fermi-gas description (as I will review), mirror symmetry is simply a canonical transformation on the phase space of the fermions.

Kazuo Hosomichi (NTU) "Surface operators in 4d N=2 gauge theories"

I will review some of the recent exact results for surface operators in 4D N=2 SUSY gauge theories.

Minxin Huang (CUST) "Topological strings on elliptic Calabi-Yau three-folds"

Chris Hull (Imperial) "The Geometry of Double Field Theory"

Norihiro Iizuka (Yukawa) "What does condensed matter physics tell us about general relativity?"

In this talk, we discuss and solve simple paradox where basic facts between condensed matter physics and general relativity(apparently) contradict through holography.

Hee-Cheol Kim (Perimeter) "The Superconformal Index of the (2,0) Theory with Defects"

In this talk, I will present how to compute the supersymmetric partition function of the six-dimensional (2,0) theory of type A_{N−1} on S1×S5 in the presence of both codimension two and codimension four defects. I will focus on a limit of the partition function depending on a single parameter. From the allowed supersymmetric configurations of defects the results show a precise match with the characters of irreducible modules of WN algebras and affine Lie algebras of type A_{N−1}.

Seok Kim (SNU) “Self-dual strings of 6d SCFTs”

I will discuss the 2d gauge theory descriptions of the self-dual strings of the 6d SCFTs. The case of E-strings will be discussed in detail, which are the self-dual strings of the 6d CFT for the M5-M9 system. In particular, I will explain that the gauge theory allows us to exactly compute the elliptic genera of the E-strings.

Dario Martelli (KCL) “Exact results in supersymmetric field theories and holography”

I will overview some exact results in supersymmetric field theories, focussing on the localization technique in four dimensional gauge theories. After reviewing supersymmetric field theories on curved manifolds and localization, I will discuss applications including supersymmetric indices and the supersymmetric Casimir energy. Time permitting, I will conclude discussing the holographic counterpart of these results and some open questions.

Noppadol Mekareeya (CERN) "Coulomb branch and the moduli space of instantons"

I will explain how to compute the Hilbert series that counts chiral operators parametrising the Coulomb branch of the moduli space of 3d N=4 supersymmetric field theories. The formula has applications to physics, such as to the study of infrared dualities in three dimensions and of backgrounds with eight supercharges, as well as to mathematics, where it provides a new way to characterise hyperKahler cones as algebraic varieties. I will then show how the Coulomb branch of certain d=3 N=4 generalised quiver gauge theories can be used to compute the Hilbert series of the moduli space of k G-instantons, for any simple Lie group G. The construction is alternative to the ADHM construction that is only available for classical groups G.

Shiraz Minwalla (TIFR) "Scattering in Large N matter-Chern-Simons Theories"

Costis Papageorgakis (QMUL) "Instanton operators in 5D gauge theories" 

We will discuss instanton operators in 5D Yang-Mills gauge theories. These are defined as local operators which create a non-vanishing second Chern class on a four-sphere surrounding their insertion point. As such they may be thought of as higher-dimensional analogues of 3D monopole (or ‘t Hooft) operators. We argue that they play an important role in the enhancement of the Lorentz symmetry for maximally supersymmetric Yang-Mills to SO(1, 5) at strong coupling.

Jaemo Park (Postech) "General instanton counting and 5d/6d SCFT"

Instanton partition functions of 5d N = 1 gauge theories are Witten indices for the ADHM gauged quantum mechanics with (0, 4) SUSY. We derive the integral contour prescriptions for these indices using the Jeffrey-Kirwan method, for gauge theories with hypermultiplets in various representations. The results can be used to study various 4d/5d/6d QFTs. In this paper, we study 5d SCFTs which are at the UV fixed points of 5d SYM theories. In particular, we focus on the Sp(N) theories with Nf ≤ 7 fundamental and 1 antisymmetric hypermultiplets, living on the D4-D8-O8 systems. Their superconformal indices calculated from instantons all show E(Nf+1) symmetry enhancements. We also discuss some aspects of the 6d SCFTs living on the M5-M9 system. It is crucial to understand the UV incompleteness of the 5d SYM, coming from small instantons in our problem. We explain in our examples how to fix them. As an aside, we derive the index for general gauged quantum mechanics with (0, 2) SUSY.

Jeong-Hyuck Park (Seogang) "Stringy Differential Geometry and Double Field Theory"

The talk introduces a stringy differential geometry beyond Riemann which underlies Double Field Theory.

Rak-Kyeong Seong (KIAS) “Mass-deformed Brane Tilings and M2-brane theories revisited”

Alessandro Tomasiello (Bicocca) “Six-dimensional superconformal theories in string theory”