Conveners
Parallel Session 3: Strings & Mathematical Physics
- Jan Plefka
Parallel Session 3: Strings & Mathematical Physics
- Jan Plefka (Humboldt University Berlin)
Parallel Session 3: Strings & Mathematical Physics
- There are no conveners in this block
Parallel Session 3: Strings & Mathematical Physics
- There are no conveners in this block
Parallel Session 3: Strings & Mathematical Physics
- There are no conveners in this block
Dr
Stefan Fredenhagen
(MPI for Gravitational Physics)
26/09/2012, 14:00
Strings & Mathematical Physics
Higher-spin gauge theories become particularly simple in 2+1 dimensions, where there are no propagating degrees of freedom. Nevertheless they are useful toy models to study e.g. higher-spin generalisations of black holes or holographic dualities. Most of the research on this subject has been done in the frame-like formalism with generalised vielbeins and spin connections. I will report on...
Dr
Rutger Boels
(II. institut für theoretische physik)
26/09/2012, 14:30
Strings & Mathematical Physics
Calculating scattering amplitudes in a flat background is one of the first things to learn in string theory: the subject started after all with Veneziano's amplitude. Beyond four external legs however explicit computations get prohibitively complex quickly using standard world-sheet methods. In this talk I will show how one can use on-shell super-symmetry in type IIB superstring theory to...
Dr
Jonathan Shock
(Max Planck Institute)
26/09/2012, 15:00
Strings & Mathematical Physics
It has been shown by Chernodub et al. that the rho meson of QCD in the presence of a very large magnetic field condenses, giving a superconducting ground state. The solution takes on a lattice form of an Abrikosov type. We calculate the holographic dual of this phenomenon. In particular we show that for magnetic fields close to the critical value, the lattice takes on a triangular form, in...
Dr
Ingo Kirsch
(DESY Hamburg)
26/09/2012, 15:50
Strings & Mathematical Physics
I discuss two-point functions on the torus in the SU(2)
Wess-Zumino-Witten model. I construct an explicit expression
for the current blocks of the spin-k/2-spin-k/2 torus
two-point function. As a first check, I consider the factorization
limits of the current blocks as well as their monodromy properties.
I then prove that the current blocks solve the corresponding
...
Dr
Oliver Schlotterer
(AEI Potsdam)
26/09/2012, 16:10
Strings & Mathematical Physics
String corrections to open superstring tree level amplitudes take a striking and elegant form once the contributions from different classes of multiple zeta values are appropriately disentangled. This novel organization of the alpha prime expansion makes use of a Hopf algebra structure underlying the motivic version of multiple zeta values: It induces an isomorphism which casts the amplitudes...
Mr
Stephan Steinfurt
(Max-Planck-Institute for Physics, Munich)
26/09/2012, 16:30
Strings & Mathematical Physics
We describe the holographic computation of supercharge diffusion constants in theories dual to gravitational theories on the background of AdS black brane solutions (of arbitrary dimension and at vanishing chemical potential for R charges).
The computation is performed via the low frequency, low momentum pole of the correlator of supercurrents, which describes the hydrodynamic "phonino" mode,...
Dr
carlo Meneghelli
(Fachbereich Mathematik uni hamburg and DESY)
26/09/2012, 16:50
Strings & Mathematical Physics
I will discuss a systematic approach to the construction of lattice regularizations of a certain class of 1+1 dimensional integrable quantum field theories.
The method is based on the identification of the relevant algebraic structure combined with a systematic analysis of its representations.
I will focus on the example of affine Toda theories.
Remarkable factorization/fusion properties of...
Prof.
Gabriele Honecker
(Johannes-Gutenberg-Universität Mainz)
27/09/2012, 14:00
Strings & Mathematical Physics
D6-brane models provide a geometrically intuitive picture for string model building. Rigid D-branes on orbifolds with discrete torsion are of particular interest due to the absence of (some) moduli on the one hand and the power of CFT tools on the other hand.
In this talk, recent progress on constructing the Standard and GUT Models in such D-brane scenarios will be presented.
Hans Jockers
(BCTP, Bonn)
27/09/2012, 14:30
Strings & Mathematical Physics
String compactifications and string model building have mainly been pursued on Calabi–Yau manifolds of a certain type: complete intersections in toric varieties. A powerful tool to study such Calabi-Yau manifolds is provided by the two-dimensional gauged linear sigma model with abelian gauge groups. In this talk I consider gauged linear sigma models with non-abelian gauge groups so as to...
Tristan McLoughlin
(MPI Potsdam)
27/09/2012, 15:00
Strings & Mathematical Physics
In recent years a host of new structures, such as Yangian symmetries
and the duality between color and kinematics, have been discovered in
the study of maximally supersymmetric scattering amplitudes. It is natural to
question whether these structures can be found in a wider class of theories.
In this talk we provide evidence for analogous structures in three-dimensional
supersymmetric...
Martin Sprenger
(DESY Theory Group)
27/09/2012, 15:50
Strings & Mathematical Physics
In this talk, I will investigate n-gluon scattering amplitudes in the multi-Regge region of N=4 supersymmetric Yang-Mills theory at strong coupling. To leading order, the amplitude at strong coupling is given in terms of a minimal surface in AdS5. The area of this surface can be calculated by a set of non-linear integral equations, which, however, do not allow an analytic solution for...
Dr
Livia Ferro
(Humboldt University of Berlin)
27/09/2012, 16:10
Strings & Mathematical Physics
In this talk I will present some work in progress on the interplay between scattering amplitudes in N=4 SYM and the Yang-Baxter equation. I will start by reviewing the notions of Yangian symmetry and Grassmannian formulation and recall the recently observed connection between the leading part of the dilatation operator for the integrable spin chain and the tree-level amplitudes. I will then...
Sebastian Halter
(LMU & ASC, Munich)
27/09/2012, 16:30
Strings & Mathematical Physics
We propose a new model of D3-brane inflation in a recently constructed class of warped throat backgrounds of Type IIB Supergravity, which are modifications of the Klebanov-Strassler background in the IR region. The dilaton has a non-trivial profile along the radial direction and induces a potential for the D3-brane. This contribution to the D3-brane potential generically features an inflection...
Mr
Alexander Knochel
(ITP Heidelberg)
27/09/2012, 16:50
Strings & Mathematical Physics
We interpret the recently discovered Higgs candidate as a standard Higgs Boson originating from an underlying string-derived supersymmetric theory.
The observed mass range of 124...126 GeV points towards a vanishing quartic coupling at intermediate to high scales. This compels us to study a class of String/F-Theory based models in which symmetries enforce a vanishing quartic Higgs coupling...
Mr
Christoph Sieg
(Humboldt U. Berlin)
27/09/2012, 17:40
Strings & Mathematical Physics
In the talk I will motivate why direct perturbative calculations in N=4 SYM theory and in ist (super9 conformal deformations are of interest and I will summarize some of our recent results and work in progress.
Dr
Gang Yang
(University of Hamburg)
27/09/2012, 18:00
Strings & Mathematical Physics
Form factors are very interesting observables to consider. For example, it has been shown that the two-loop form factor in N=4 SYM is equal to the leading transcendental part of a Higgs scattering amplitude in QCD. In this talk we report some progress on computing form factors in N=4 SYM at strong coupling based on AdS/CFT duality.
Mr
Steffen Mueller
(Max-Planck Institute for Physics)
27/09/2012, 18:20
Strings & Mathematical Physics
Gauge/gravity duality has proved to be a very successful tool for
describing strongly coupled systems in particle physics and heavy ion
physics. The application of the gauge/gravity duality to quantum matter is a promising candidate to explain questions concerning non-zero temperature dynamics and transport coefficients. To a large extent, the success of applications of gauge/gravity duality...
Mr
Daniel Plencner
(LMU Munich)
27/09/2012, 18:40
Strings & Mathematical Physics
D-branes on Calabi-Yau manifolds can be described by matrix factorizations at the Landau-Ginzburg (LG) point. In this talk I will discuss methods for the study of D-brane moduli spaces and superpotentials within this framework. An emphasis will be put on non-toric complex structure deformations, which arise as bulk moduli from twisted sectors in the LG orbifold. I will outline how the...
