“String Theory and Conformal Field Theory”

Spring Semester 2007

Wednesday, 14:00, HPZ E9

Organised by: Ilka Brunner and Matthias Gaberdiel

day
date
time
venue
speaker
title
Wed
28.03.
14:00
HPZ E9
Manfred Herbst (DESY)
“Phases of N=2 theories in two dimensions with boundaries”
Wed
04.04.
14:00
HPZ E9
Marlene Weiss (CERN)
“Direct integration of the topological string”
Thu
19.04.
14:00
HPZ E9
Iosif Bena (Saclay)
“Black rings, geometric transitions and typical black hole microstates”
abstract (click to view) I will describe the construction of BPS solutions that describe black rings as well as "black hole microstates" - smooth horizonless solutions that have the same charges and the same angular momenta as the three-charge 5D BPS black hole. I will then use properties of these solutions to argue that all the states of the dual CFT should be dual to horizonless configurations, and therefore the black hole solution should be thought of as a thermodynamic description of an ensemble of such configurations, that stops giving a valid description of the physics at the scale of the horizon. (click to hide)
Wed
25.04.
14:00
HPZ E9
Hans Jockers (CERN)
“Matrix factorisations, vector bundles and D-brane monodromies”
Wed
09.05.
14:00
HPZ E9
Stephan Stieberger (MPI Munich)
“Multi-Gluon Scattering and MHV Amplitudes in Superstring Theory”
abstract (click to view) We discuss the amplitudes describing N-gluon scattering in superstring theory, on a disk world-sheet. These amplitudes probe higher order gauge interactions with N external legs on Dp-branes. The full string S-matrix results may be nicely summarized in a very compact and intriguing form capturing the alpha'-expansion of the effective action. A subsector of these amplitudes, namely their maximally helicity violating (MHV) part, generalizes recently discussed properties in twistor space including alpha'-corrections. Furthermore we find other intriguing relations. If nature picked a sufficiently low string mass scale, our results would be important for studying string effects in multi-jet production at the Large Hadron Collider (LHC). We present mathematical tools for computing multiple gluon open superstring disk amplitudes: a systematic and efficient method to calculate tree-level string amplitudes and relations between multiple hypergeometric functions and their alpha'-(momentum)-expansions given by (generalized) multiple Euler-Zagier sums. (click to hide)
Wed
30.05.
14:00
HPK D24.2
Henning Samtleben (ENS Lyon)
“Gauged supergravity and U-duality”
Wed
06.06.
13:30
HPZ E9
Ivo Sachs (LMU Munich)
“Chiral Symmetry Breaking in AdS/CFT”
abstract (click to view) We analyze stringy generalizations of the large N Gross-Neveu and NJL model at strong coupling in terms of probe branes in the gravity dual. This leads to a phase diagram which is in qualitative agreement with field theory expectations. In addition a Landau effective potential for the order parameter is obtained by taking the profile of the probe brane off-shell. Finally we identify the Goldstone boson associated with the chiral symmetry breaking. (click to hide)

last modified: Sun, 1 Jun 2014, 08:24 CEST

Winter Semester 2007

Wednesday, 14:00, HPZ E9

Organised by: Ilka Brunner and Matthias Gaberdiel

day
date
time
venue
speaker
title
Wed
03.10.
14:00
HPZ G2
Stefan Hohenegger (ETH Zurich)
“Topological amplitudes and string effective couplings”
Wed
17.10.
14:00
HPZ E9
Esko Keski-Vakkuri (University of Helsinki)
“Rolling tachyons, random matrices and Coulomb gas thermodynamics”
Wed
24.10.
14:00
HPZ E9
Daniel Krefl (LMU München)
“Dimers & Orientifolds”
Fri
02.11.
11:30
HPZ E9
various
GeNeZiSS meeting: t.b.a.
Wed
21.11.
14:00
HPZ E9
Finn Larsen (Michigan & CERN)
“Resolving Gravitational Singularites”
abstract (click to view) In some situations higher derivative interactions modify the leading order physics significantly. For a class of black holes in string theory the important terms are singled out by anomalies and supersymmetry. Quantitative computations are possible using the explicit supersymmetric Lagrangian. In some cases the higher derivative corrections resolve singularities in the leading order result in a controlled manner. (click to hide)
Wed
28.11.
14:00
HPZ E9
Neil Lambert (King's College London)
“Modeling Multiple M2-branes”
Wed
05.12.
14:00
HPZ E9
Christian Roemelsberger (LMU München)
“Calculating the Superconformal Index and Seiberg Duality”
Wed
12.12.
14:00
HPZ E9
Amit Giveon (Hebrew University)
“On the Landscape in SQCD and its Embedding in String Theory”
Wed
09.01.
14:00
HPZ E9
Ingo Runkel (King's College London)
“Perturbed defects and functional relations in conformal field theory”

last modified: Sun, 1 Jun 2014, 08:25 CEST

Spring Semester 2008

Wednesday, 14:00, HPZ E9

Organised by: Ilka Brunner, Matthias Gaberdiel and Johannes Walcher

day
date
time
venue
speaker
title
Wed
20.02.
14:00
HPZ E9
Minxin Huang (CERN)
“Topological strings, black holes and matrix models”
Wed
27.02.
14:00
HPZ E9
Terry Gannon (University of Alberta)
“Galois and finite groups”
abstract (click to view) The Galois action on character tables of finite groups has been known for a century. I describe the geometry underlying it, and explain how it fits into the first window of an infinite tower of increasingly intricate Galois actions related to finite groups. This question and answer was motivated by understanding the Galois action in rational conformal field theory. (click to hide)
Wed
05.03.
14:00
HPZ E9
Raphael Benichou (ENS Paris)
“Non-compact Gepner Models, Landau-Ginzburg Orbifolds and Mirror Symmetry”
Wed
12.03.
14:00
HPZ E9
Pedro Vieira (ENS Paris & Porto)
“Quantum Wrapped Giant Magnon”
Wed
19.03.
14:00
HPZ E9
Sergey Cherkis (Trinity College, Dublin)
“Bows and Quivers: from Impurity Theories to Instantons on Curved Backgrounds”
abstract (click to view) We propose a formalism generalizing the ADHM construction. The new construction is formulated in terms of Bow diagrams. It is motivated by string theory dualities and analysis of effective gauge theories with inhomogeneities of codimension one. To illustrate the construction we obtain the explicit metric on the moduli space and gauge fields of one instanton on the Taub-NUT space. (click to hide)
Wed
02.04.
14:00
HPZ E9
Jan Plefka (Humboldt Universität Berlin)
“The quantum AdS_5xS^5 superstring in light-cone”
Wed
09.04.
14:00
HPZ E9
Jan Manschot (University of Amsterdam)
“Construction of partition functions for AdS3/CFT2”
abstract (click to view) The partition function of (super)gravity in AdS3 is expected to equal the partition function of a dual conformal field theory by the AdS/CFT correspondence. I explain how the CFT partition function can be rewritten as a modular sum, which can be interpreted as a sum over geometries. The part of the spectrum of AdS3-gravity which lies below the cosmic censorship bound is of particular importance to construct the full partition function by the modular sum. Modular invariance is shown to impose constraints on the degeneracies of this part of the spectrum. (click to hide)
Wed
16.04.
14:00
HPZ E9
Johannes Henn (Annecy)
“Wilson loop / gluon amplitude duality in N=4 SYM”
abstract (click to view) I am going to talk about an intriguing new duality between planar MHV gluon amplitudes and light-like Wilson loops in N=4 super Yang-Mills. We derive an all-order broken conformal Ward identity for the Wilson loops and analyse its consequences. Starting from six points, the Ward identity allows for an arbitrary function of conformal invariants. We compute this function at six points and two loops and discuss its implications for the corresponding gluon amplitude. (click to hide)
Wed
23.04.
14:00
HPZ E9
Roberto Volpato (Padova)
“CFT correlators and canonical curves”
Wed
30.04.
14:00
HPZ E9
Ben Craps (Vrije Universiteit Brussels)
“Quantum resolution of cosmological singularities using AdS/CFT”
Tue
06.05.
14:00
HCI J6
Rajesh Gopakumar (Harish-Chandra Institute, Allahabad)
“Free fermions and Thermal AdS/CFT”
Thu
15.05.
14:00
HPP G7
Andy Neitzke (IAS Princeton)
“Wall-Crossing Phenomena in Two and Four Dimensions”
Wed
21.05.
14:00
HPZ E9
Samuel Monnier (Geneva)
“Kondo flow invariants from super Wess-Zumino-Witten boundary states”
Wed
28.05.
14:00
HPZ E9
Carlos Nunez (Swansea University)
“Recent developments in gauge-string duality”
Wed
04.06.
11:30
HPZ E9
Suvankar Dutta (Harish-Chandra Institute, India)
“Higher Derivative Corrections to Locally Black Brane Metrics”
abstract (click to view) In this talk we will generalize the construction of locally boosted black brane space time to higher derivative gravities. We will consider the Gauss-Bonnet term (with coefficient alpha') as a toy example. We will find the solution to the alpha' corrected Einstein equations to first order in the boundary derivative expansion. This allows us to find the alpha' corrections to the boundary stress tensor in the presence of the Gauss-Bonnet term in the bulk action. We will therefore obtain the ratio of shear viscosity to entropy which agrees with other methods of computation in the literature. (click to hide)
Wed
04.06.
14:00
HPZ E9
Nabamita Banerjee (Harish-Chandra Institute, India)
“Aspects of Dyon Degeneracy Function in N=4 Theories”

last modified: Sun, 1 Jun 2014, 08:25 CEST

Fall Semester 2008

Wednesday, 14:00, HIT K51

Organised by: Matthias Gaberdiel

day
date
time
venue
speaker
title
Wed
15.10.
14:00
HIT K51
Alfonso Ramallo (Santiago de Compostela)
“The supergravity dual of N=4 gauge theories in two dimensions”
abstract (click to view) We will present supergravity duals to field theories in two dimensions with N=(4,4) SUSY which reproduce certain aspects of the dual field theory with a large number of colors and a tunable number of flavors. Different aspects of the two-dimensional field theory are discussed, among them the running of gauge couplings and the spectrum of mesons in Higgs and Coulomb branches. (click to hide)
Wed
22.10.
14:00
HIT K51
Max Kreuzer (TU Wien)
“Geometry and combinatorics of hidden dimensions”
abstract (click to view) After a brief introduction about how phenomenological prejudices imply interesting complex and generalized geometries for hidden dimensions I explain the combinatorial basics of the construction of Calabi-Yau manifolds in toric ambient spaces and show how the conjectured connectedness of the space of all Calabi-Yau 3-folds can be used to explore unknown territory. (click to hide)
Wed
29.10.
14:00
HIT K51
Vasilis Niarchos (Polytechnique)
“Notes on the Dynamics of N=2 Chern-Simons-Matter Theories”
abstract (click to view) I will review the basic structure of N=2 supersymmetric Chern-Simons gauge theories coupled to matter and discuss some of their most striking properties: the existence of conformal fixed points, large anomalous dimensions, spontaneous SUSY breaking and a weak/strong Seiberg duality. (click to hide)
Wed
05.11.
14:00
HIT K51
Daniel Persson (ULB Brussels)
“Compactification of Higher Derivative Corrections and Automorphic Forms”
abstract (click to view) Toroidal compactification of supergravity reveals a hidden global symmetry G(R) in three dimensions. In this talk I will discuss how discrete U-duality subgroups G(Z) in D=3 can be used to analyze non-perturbative contributions to the effective action. In particular, we consider the compactification to three dimensions of higher derivative corrections, and show through general arguments that the symmetry group G(R) is explicitly broken in the resulting action. I will then argue that invariance under a discrete subgroup G(Z) may be restored upon including non-perturbative effects. This "non-perturbative completion" requires the introduction of G(Z)-invariant automorphic forms. After this general discussion we consider the explicit example of quartic derivative corrections to the universal sector of IIA Calabi-Yau compactifications, which at the two-derivative level exhibits a global SU(2,1)-symmetry upon reduction to D=3. In this setup one may explicitly construct an automorphic form invariant under a discrete subgroup of SU(2,1), which incorporates the contribution from expected D2- and NS5-brane instanton effects. (click to hide)
Wed
03.12.
14:00
HIT K51
Benoit Vicedo (Cambridge)
“A Symplectic Structure for String Theory on Integrable Backgrounds”
Wed
10.12.
14:00
HIT K51
Thomas Creutzig (DESY Hamburg)
“Wess-Zumino-Witten models on Lie supergroups”
abstract (click to view) There are two approaches to Wess-Zumino-Witten models on Lie supergroups (of type I) in terms of free fermions. I will present them in the prototypical example of the bulk and boundary GL(1|1) model and comment on generalizations to other supergroups. (click to hide)
Thu
11.12.
14:00
HIL B21
Vladimir Mitev (DESY Hamburg)
“Dualities in supersymmetric sigma models”
abstract (click to view) Sigma models with supergroup target space symmetry can have very peculiar properties allowing the exact computation of their spectra and the discovery of dual descriptions. The cases of the superspheres and the complex projective superspaces are presented in detail. (click to hide)
Tue
16.12.
14:00
HIT K52
Susanne Reffert (IPMU)
“Quantum Crystals, Spin Chains, and Topological Strings”
abstract (click to view) Starting from earlier works on the subject (Classical Crystal and Quantum Calabi-Yau, Quantum Foam and Topological Strings), we study the correspondence between the statistical system of a melting crystal corner and topological string theory. We propose a quantum Hamiltonian governing the melting process of the quantum crystal. Its ground state reproduces the steady state distribution of the classical system. The quantum analog of the system of Young diagrams turns out to correspond directly to the XXZ spin chain, an integrable system. I will discuss the properties of these systems as well their relation to stochastic quantization, and implications for topological string theory. (click to hide)
Wed
17.12.
14:00
HIT K51
Kyriakos Papadodimas (Amsterdam)
“The chiral ring of AdS3/CFT2 and the attractor mechanism”

last modified: Sun, 1 Jun 2014, 08:25 CEST

Spring Semester 2009

Wednesday, 14:00, HIT F11.1

Organised by: Matthias Gaberdiel

day
date
time
venue
speaker
title
Wed
25.02.
14:00
HIT K51
Rutger Boels (Niels Bohr Institute Copenhagen)
“Buzzword bingo: MHV, CSW and BCFW in string amplitudes”
abstract (click to view) In recent years there have been quantum leaps in the development of calculational technology for field theory amplitudes, partly captured by the buzzwords in the title of this talk. Interestingly, most of these developments are rooted within field theory ideas of the sixties which centered around the 'analytic S-matrix'. This line of thought led to the birth of string theory with Veneziano's amplitude. It therefore seems a natural question if these recent field theory ideas can be found within the frame-work of string theory amplitudes. On the basis of three examples, I will argue that this is not only natural but profitable. (click to hide)
Wed
11.03.
14:00
HIT F11.1
Olaf Lechtenfeld (University of Hannover)
“N=4 mechanics, WDVV equations and roots”
Fri
20.03.
14:00
HIT J52
Arjun Bagchi (HRI Allahabad, India)
“Galilean Conformal Algebras and AdS/CFT”
Wed
25.03.
14:00
HIT F11.1
Tomas Ortin (UAM Madrid)
“The tensor hierarchy of N=1,d=4 gauged supergravity”
Wed
01.04.
14:00
HIT F11.1
Romuald Janik (Jagellonian University, Krakow)
“Perturbative gauge theory results from the AdS/CFT correspondence”
abstract (click to view) I will describe recent work which enables to obtain, directly from string theory in AdS_5xS^5, results of four loop perturbative computations in gauge theory. The agreement between the two very different computations is a nontrivial test of the AdS/CFT correspondence. (click to hide)
Wed
08.04.
14:00
HIT F11.1
Atish Dabholkar (LPTHE Paris)
“Borcherds-Kac-Moody Symmetry of N=4 Dyons”
Wed
22.04.
14:00
HIT F11.1
Murad Alim (LMU Munich)
“Mirror Symmetry, Toric Branes and Topological String Amplitudes”
abstract (click to view) In this talk a toric geometry description of open string mirror symmetry and the underlying N=1 special geometry will be discussed. Furthermore a polynomial recursive construction of higher genus topological amplitudes for closed strings as well as for a certain critical locus of open string moduli space is presented. (click to hide)
Wed
29.04.
14:00
HIT F11.1
Nicolas Orantin (CERN)
“Topological recursion, matrix models and topological strings”
Wed
13.05.
14:00
HIT F11.1
Marco Matone (Padua)
“(Super)string Measure and Characterization of Jacobians”
abstract (click to view) Integrating the (Super)string measure on the moduli space of Riemann surfaces requires the characterization of the locus of period matrices in the Siegel upper half-space (Schottky problem). The unique case for which an explicit solution is known is for genus four, where such a locus is characterized by the vanishing of the Schottky-Igusa modular form. Such a form is the same that defines the Polyakov-Mumford form, the cosmological constant and the quadric embedding the Riemann surface in a projective space, whose discriminant corresponds with the square root of the product of all theta constants with even characteristic. Genus dependent powers of the latter provide the Polyakov-Mumford form in the known cases of low genus. This indicates that finding the Polyakov-Mumford form, the cosmological constant and the modular forms vanishing on the Jacobian locus are deeply related problems at any genus. In particular, we provide some evidence that the Mumford isomorphism and the geometry of quadrics embedding Riemann surfaces in projective spaces provide the key to answer such questions. (click to hide)
Wed
20.05.
14:00
HIT F11.1
Peter West (King's College London)
“E theory”
abstract (click to view) I will review the conjecture that string theory should possess an underlying E_11 symmetry. This will include a summary of the evidence for the conjecture and a discussion of the interplay between space-time, locality and E_11. (click to hide)
Wed
27.05.
14:00
HIT F11.1
Alexander Sevrin (VUB, Brussels)
“Generalized lagrangian and coisotropic branes”
Mon
29.06.
14:00
HIT K51
Carlos Cardona Giraldo (University of Buenos Aires)
“Spectral Flowed Three-point functions on AdS(3)xS(3)xT(4)”

last modified: Sun, 1 Jun 2014, 08:25 CEST

Fall Semester 2009

Wednesday, 14:00, HIT K51

Organised by: Matthias Gaberdiel

day
date
time
venue
speaker
title
Wed
07.10.
14:00
HIT K51
Fernando Alday (Princeton)
“Liouville Correlation Functions from Four-dimensional Gauge Theories”
Wed
04.11.
14:00
HIT K51
Niclas Wyllard (Chalmers Univ. of Technology)
“Matrix models, N=2 gauge theories and Toda field theories”
Wed
11.11.
14:00
HIT K51
Pietro Antonio Grassi (Universita del Piemonte Orientale, Alessandria)
“Pure Spinors and Superdualities”
Wed
18.11.
14:00
HIT K51
Peter Bantay (Eotvos University, Budapest)
“RCFT characters and differential equations”
Wed
09.12.
14:00
HIT K51
Stephan Stieberger (MPI Munich)
“Disk Scattering of Open and Closed Strings”
abstract (click to view) We establish a relation between disk amplitudes involving N_o open and N_c closed strings and disk amplitudes with only N=N_o+2N_c open strings. This map, which represents a sort of generalized Kawai-Lewellen-Tye relation on the disk, reveals important structures between open & closed and pure open string disk amplitudes: it relates couplings of brane and bulk string states to pure brane couplings. On the string world-sheet this becomes a non-trivial monodromy problem, which reduces the disk amplitude of N_o open and N_c closed strings to a sum of many color ordered partial subamplitudes of N_o+2N_c open strings. Hence, the computation of disk amplitudes involving open and closed strings is reduced to computing color ordered N-point subamplitudes in the open string sector. In this sector we find a string theory generalization and proof of the Kleiss-Kuijf and Bern-Carrasco-Johannson relations: All order alpha' identities between open string subamplitudes are derived, which reproduce these field-theory relations in the limit alpha'->0. These identities allow to reduce the number of independent subamplitudes to a minimal basis describing the full N-point open string amplitude. Equipped with these results we compute disk amplitudes involving open and closed string moduli in Calabi-Yau orientifolds with D-branes and world-volume two-form flux. These amplitudes probe the low-energy couplings and the underlying sigma model couplings of the moduli space. (click to hide)
Wed
16.12.
14:00
HIT K51
Michael Tuite (NUI Galway)
“Vertex Operator Algebras on Riemann Surfaces”
abstract (click to view) In this talk we describe the partition function (and some n-point correlation functions) for a Vertex Operator Algebra (VOA) on genus two and higher Riemann surface constructed from punctured tori. We consider the examples of the Heisenberg VOA for a free boson and continuous orbifolding of the free fermion Super VOA. This talk is based on collaborations with Geoffrey Mason and Sasha Zuevsky. (click to hide)
Fri
18.12.
14:00
HIT K51
Domenico Orlando (IPMU)
“Supersymmetry without Lorentz invariance”
abstract (click to view) Non-relativistic models have recently attracted a renewed attention in different branches of physics, from the description of quantum phase transitions to the construction of effective theories of gravity. In this talk I will show how non-relativistic systems of Lifshitz type can be understood in terms of a Brownian motion and admit a natural supersymmetrization. This provides a new set of tools to deal with technical and more conceptual aspects of these theories. (click to hide)

last modified: Sun, 1 Jun 2014, 08:25 CEST

Spring Semester 2010

Wednesday, 14:00, HIT H51

Organised by: Matthias Gaberdiel

day
date
time
venue
speaker
title
Tue
09.02.
11:00
HIT K51
Terry Gannon (University of Alberta)
“The Haagerup and the search for exotic CFTs”
Wed
03.03.
14:00
HIT H51
Ipsita Mandal (Harish Chandra Research Institute)
“Supersymmetry, Localization and Quantum Entropy Function”
Wed
10.03.
14:00
HIT H51
Roberto Volpato (ETH Zürich)
“Two point chiral amplitudes in superstring theory at higher genus”
abstract (click to view) We show that the proposed formula for the two point function in RNS superstring, based on Grushevski ansatz for the chiral measure at all genera, fails to vanish at genus four, in contrast with expectations from space-time supersymmetry. This result is strictly related to the non-vanishing of the cosmological constant at genus five. This connection may shed some light on the way the original ansatz for the superstring measure must be corrected for genus higher than four. (click to hide)
Wed
17.03.
14:00
HIT H51
Giulio Bonelli (SISSA)
“On the M-theory origin of AGT correspondence”
Wed
31.03.
14:00
HIT H51
Ilka Brunner (LMU Munich)
“Attractor flows from defect lines”
Wed
14.04.
14:00
HIT H51
Sameer Murthy (LPTHE)
“Towards a complete understanding of black hole entropy”
abstract (click to view) There has been quite some progress recently in extending the Bekenstein-Hawking black hole entropy formula to an exact formula valid at all values of charges. This extension involves many technical as well as conceptual issues. In this talk, I will first review these issues and then present some of my work in tackling them in the context of string theoretic black holes. In particular, I will discuss the computation of perturbative corrections to the area law, non-perturbative effects, moduli dependence and the issue of degeneracy v/s index. (click to hide)
Wed
05.05.
14:00
HIT H51
Giuseppe Milanesi (Bern University)
“Exact Gravitational Dual of a Plasma Ball”
abstract (click to view) I'll discuss present an exact solution for a black hole localized near an infrared wall in four- dimensional anti-deSitter space. By computing the holographic stress tensor one can show that the CFT dual of the black hole is a 2+1-dimensional ball (i.e., a disk) of plasma at finite temperature, surrounded by vacuum. This confirms some earlier conjectures about plasma balls in AdS/CFT. The value of the surface tension for the ball can be estimated. The solution displays a number of peculiarities, most notably a non-trivial curvature of the boundary geometry, as well as other properties associated to the vanishing deconfinement temperature of the set up. I'll discuss how these features are related to specific physics at the infrared and ultraviolet boundaries for this solution, and should not be generic properties of plasma balls. (click to hide)
Wed
12.05.
14:00
HIT H51
Stefan Vandoren (U. Utrecht)
“BPS Black hole solutions in N=2 D=4 gauged supergravity”
Wed
02.06.
10:30
HIT E41.1
various
Program Workshop: “Condensed Matter meets String Theory”
abstract (click to view) Program: 10.30-11.30: Markus Mueller (Trieste): Relativistic transport at strong coupling: graphene, quantum criticality and black holes; 14.00-15.00: David Tong (Cambridge): Conductivity from Lifshitz Geometries; 16.00-17.00: Vladimir Gritsev (Fribourg): Duality-based approach to disordered condensed matter systems (click to hide)
Wed
09.06.
14:00
HIT J51
Azat Gaynutdinov (Saclay)
“Lattice approach to non-chiral non-rational logarithmic CFT”
abstract (click to view) We study an affine Temperley-Lieb algebra action on a periodic spin-chain with gl(1|1) symmetry. Scaling limit of Fourier images for periodic Temperley-Lieb (TL) generators gives a non-chiral (left and right) Virasoro algebra with c=-2 which defines a non-chiral non-rational logarithmic CFT with infinitely many primary fields. Our main result on the lattice part is a theorem on the (maximum) centralizer for the periodic TL. This theorem allows to obtain a decomposition of the spin-chain into indecomposable modules over the periodic TL with non-trivial Jordan blocks for the hamiltonian. The modules are of two-strands Feigin-Fuchs type (for Virasoro). The scaling limit of the indecomposables on the lattice gives non-chiral versions of the staggered modules for chiral Virasoro algebra with non-diagonalizable L_0 and which are characterized by an infinite sequence of logarithmic couplings. We obtain a full description of field content w.r.t. left and right Virasoro in the non-rational non-chiral logarithmic theory which can be further used to classify Ishibashi states. (click to hide)
Wed
23.06.
14:00
HIT K52
Emery Sokatchev (LAPTH, Annecy)
“Superconformal invariance of scattering amplitudes in N=4 super-Yang-Mills theory”
Wed
30.06.
14:00
HIT J51
Ingo Kirsch (DESY, Hamburg)
“Worldsheet four-point functions in AdS3/CFT2”
Mon
05.07.
11:00
HIT F11.1
John McKay (Concordia University)
“A home for the finite simple groups”

last modified: Sun, 1 Jun 2014, 08:25 CEST

Spring Semester 2011

Wednesday, 14:00, HIT E41.1

Organised by: Matthias Gaberdiel

day
date
time
venue
speaker
title
Wed
16.02.
14:00
HIT E41.1
Paulina Suchanek (ETH Zürich)
“Elliptic recursive relations for conformal blocks”
abstract (click to view) I will present a short introduction to the elliptic recursion for 4-point blocks on the sphere and 1-point blocks on a torus. I will also discuss two applications of the recursive relations: a proof of the modular invariance of the Liouville theory and a proof of the AGT conjecture for irregular blocks. (click to hide)
Wed
02.03.
14:00
HIT E41.1
Thomas Zojer (Vienna)
“Three-dimensional gravity and logarithmic conformal field theories”
Wed
09.03.
14:00
HIT E41.1
Sara Pasquetti (QMU London)
“2d CFTs, N=2 theories and surface operators”
abstract (click to view) I will describe two classes of surface operators of N=2 theories and their CFT duals. The first class is realised in terms of M2 branes and it is related to open topological string amplitudes with toric branes. The second class of surface operators arises from an intersection of M5 branes. (click to hide)
Wed
16.03.
14:00
HIT E41.1
Simeon Hellerman (IPMU Tokyo)
“Kahler potentials”
Thu
07.04.
14:00
HIT E41.1
Marcos Marino (Geneva)
“Chern-Simons-matter theories at strong coupling”
abstract (click to view) It has been recently realized that the free energy of 3d QFTs on the three-sphere is a non-trivial function of the couplings which plays the role of the c-function in two-dimensional QFTs. In superconformal Chern-Simons-matter theories, this quantity can be computed in the planar limit by using localization and matrix model techniques, and one obtains in this way an exact answer interpolating between weak and strong coupling. These techniques have given us in recent months new, impressive tests of the AdS_4/CFT_3 correspondence. In this talk I will present some of these developments, focusing on the original case of the ABJM theory. I will also discuss the non-planar corrections in the ABJM theory, which make possible to discuss non-perturbative effects in the string coupling constant for the type IIA string duals. (click to hide)
Wed
13.04.
14:00
HIT E41.1
Stefan Fredenhagen (AEI Potsdam)
“Matrix factorisations for defects and boundaries in coset models”
Wed
20.04.
14:00
HIT E41.1
Albrecht Klemm (Bonn)
“Omega backgrounds and generalized holomorphic anomaly equation”
abstract (click to view) We derive an anomaly equation which incorporates the general Omega background in the B-model. We discuss applications to topological string theory on Calabi-Yau backgrounds and N=2 gauge theory with (massive) flavors. Using geometric engineering on the Enriques Calabi-Yau we derive Seiberg-Witten curves for the conformal cases, which are comptabible with Nekrasovs partition function. (click to hide)
Wed
04.05.
14:00
HIT E41.1
Hagen Triendl (CEA Saclay)
“N=1 Vacua in N=2 Supergravity and String Theory”
abstract (click to view) We discuss N=1 vacua in spontaneously broken N=2 supergravities. We start by reviewing classical no-go theorems on their existence and how these no-go theorems can be circumvented for general N=2 supergravities. We construct stable N=1 vacua for any moduli space that might arise in type II flux compactifications and discuss quantum effects in the corresponding string theory compactifications. We also show how integrating out the massive fields leads to an N=1 effective theory at low energies and discuss to which extend moduli stabilization takes place. (click to hide)
Fri
13.05.
11:30
HIT J51
James Sparks (Oxford)
GeNeZiSS meeting: “The large N limit of quiver matrix models and Sasakian manifolds”
Fri
13.05.
14:00
HIT J51
James Drummond (Annecy)
GeNeZiSS meeting: “Integrable structures in gauge theory scattering amplitudes”
Fri
13.05.
15:30
HIT J51
Misha Vasiliev (Lebedev Institute, Moscow)
GeNeZiSS meeting: “Structure of higher-spin gauge theory”
abstract (click to view) General features of interacting higher-spin gauge theories and related formalism will be explained. The four-dimensional higher-spin gauge theory will be considered in some detail. Recent results on higher-spin black hole and the formulation in the extended matrix space will be mentioned in the end. (click to hide)
Wed
25.05.
14:00
HIT E41.1
Jan Manschot (CEA Saclay)
“A fixed point formula for the index of multi-centered N=2 black holes”
Wed
01.06.
14:00
HIT E41.1
Aalok Misra (IIT Roorkee)
“Large Volume Cosmo-Pheno Reconciliation, mu-Split SUSY and Ricci-flat Swiss Cheese Metrics”
abstract (click to view) Starting with type IIB string theory compactified on an orientifold of a Swiss-Cheese Calabi-Yau expressed as a degree-18 hypersurface in the weighted complex projective space WCP^4[1,1,1,6,9], in the presence of a mobile space-time filling D3-brane and fluxed [stack(s) of] space-time filling D7-brane(s) wrapping the 'big' (as opposed to the 'small') divisor, we give a geometric proposal for obtaining a super-massive gravitino in the inflationary epoch and a "light" gravitino in the present era in a single setup. We also show that the setup naturally realizes a "mu-split supersymmetry scenario" wherein having restricted the mobile D3-brane to the big divisor, one obtains super-massive D3-brane positon moduli - identified as the two Higgs doublets - at the string scale and after 1-loop Nath-Arnowitt RG-evolution to the EW scale, one obtains one light and one super-massive Higgs doublet. Also, the fermions (quarks/leptons) corresponding to the fermionic super-partners of the Wilson line moduli, are very light but the Higgsino mass parameter is very large. I also discuss issues like neutrino masses, gluino and proton decays. As a bonus, I will discuss obtaining the geometric Kaehler potential (relevant to the moduli space Kaehler potential in the presence of a mobile D3-brane) corresponding to a Ricci-flat metric for the Swiss-Cheese Calabi-Yau used in the large volume limit using Gauged Linear Sigma Model techniques for obtaining the geometric Kaehler potential for the big divisor, and the Donaldson's algorithm for obtaining Ricci-flat metrics, as guides. (click to hide)
Wed
08.06.
14:00
HIT E41.1
Neil Lambert (CERN)
“M5's, D4's and 5D SYM”
abstract (click to view) In this talk I will revisit the relation of the six-dimensional (2,0) theory to 5-dimensional maximally supersymmetric Yang-Mills Theory. In particular it will be suggested that the latter theory has all the required states associated to the former theory when compactified on a circle. This in turn suggests that 5D Super-Yang-Mills is potentially an interesting theory, possible finite, or with only a relatively minimal UV completion. (click to hide)

last modified: Sun, 1 Jun 2014, 08:25 CEST