Europhysics Conference on High-Energy Physics 2011

Session

Non-Perturbative QFT and String Theory

Non-Perturbative QFT and String Theory

23 juil. 2011, 09:00

Dauphine (Alpes Congrès - Alpexpo)

269. Improved Holographic QCD

Elias Kiritsis (UoC and APC)

23/07/2011 09:00

Parallel session talk

We propose holographic models based on Einstein-dilaton gravity with a potential in 5 dimensions. Such theories, for a judicious choice of potential are very close to the physics of large-N YM theory both at zero and finite temperature. The zero temperature glueball spectra as well as their finite temperature thermodynamic functions compare well with lattice data. The model can be used to...

563. The characteristics of thermalization of boost-invariant plasma from holography

Dr Michal Heller (Universiteit van Amsterdam / Institute for Nuclear Studies)

23/07/2011 09:30

Parallel session talk

We report on the evolution of boost-invariant N=4 super Yang-Mills plasma covering a large range of proper times starting from various nonequilibrium states at tau=0, through a transition to a hydrodynamic regime and following subsequent hydrodynamic expansion. The results are obtained through numerical solution of Einstein's equations for the dual geometries. Despite the very rich far from...

260. Phenomenology of irreversible processes from gravity

Dr Ayan Mukhopadhyay (LPTHE, University of Paris VI, France)

23/07/2011 09:45

Parallel session talk

We argue, using inputs from both field theory and gravity, that all non-equilibrium phenomena holographically dual to solutions of pure gravity, are determined completely by a closed set of equations of motion of the energy-momentum tensor. These phenomenological equations include energy-momentum conservation, but additional equations for evolution of the shear-stress tensor also. A class of...

33. The Asymptotic Safety Program for Quantum Gravity

Dr Frank Saueressig (Institut für Physik, Johannes Gutenberg Universität Mainz)

23/07/2011 10:00

Parallel session talk

Weinberg's asymptotic safety scenario proposes that gravity constitutes a consistent and predictive Quantum Field Theory within Wilson’s generalized framework of renormalization. The key ingredient in the construction is a non-trivial fixed point of the gravitational renormalization group flow which controls the UV behavior of the theory and renders it safe from unphysical divergences. This...

565. F-theory and Model Building

Dr Andres Collinucci (LMU, Munich)

23/07/2011 11:00

Parallel session talk

F-theory was developed in the mid-nineties as a tool to study IIB string theory beyond its perturbative regime. Although conceptually less understood than its "spouse", M-theory, F-theory is a more practical tool for model building mainly because it is anchored to algebraic geometry. This well-studied field of mathematics facilitates spectacularly detailed calculations and provides for endless...

153. Proton decay and wavefunctions in F-theory GUTs

Dr Eran Palti (Ecole Polytechnique)

23/07/2011 11:30

Parallel session talk

We study proton decay in Grand Unified Models based on F-theory. We calculate the coupling of the heavy Higgs triplet modes to the light quark generations. This coupling plays an essential part in dimension 5 proton decay and we show that it is very different from the associated Yukawa coupling.

65. Testing string vacua in the lab: large extra dimensions and hidden photons

Dr Michele Cicoli (DESY, Hamburg)

23/07/2011 11:45

Parallel session talk

We present examples of string compactifications with an anisotropic shape of the extra dimensions which are very promising to make contact with current experiments since they allow the existence of micron-sized extra dimensions, TeV scale strings and hidden Abelian gauge bosons with a kinetic mixing with the ordinary photon.

267. Stringy signatures at colliders

Dieter Luest (Max-Planck-Institut fuer Physik, Ludwig-Maximilians-Universitaet)

23/07/2011 12:00

Parallel session talk

In this talk I will discuss possible stringy signatures at hadron colliders. I will concentrate on D-brane models with a low string scale in the TeV region. The production of string resonances in di-jet events as well as leptophobic Z'-gauge bosons will be discussed. Also some more formal aspects of low string scale compactifications in connection with black holes will be mentioned at the end.

84. Towards exact field theory results for the Standard Model on fractional D6-branes

Gabriele Honecker (Universitaet Mainz)

23/07/2011 12:30

Parallel session talk

Fractional D6-branes on toroidal orbifold backgrounds are known to be able to accommodate the particle spectrum and gauge group of the Standard Model, but up to now exact results for their low-energy effective action are missing. In this talk, I will discuss how the conceptual ansatz for the field theory on the torus is generalised to those orbifold backgrounds on which the Standard Model...

263. Non-perturbative transitions among intersecting-brane vacua

Dr Cezar Condeescu (CPHT - Ecole Polytechnique)

23/07/2011 12:45

Parallel session talk

We investigate the transmutation of D-branes into Abelian magnetic backgrounds on the world-volume of higher-dimensional branes, within the framework of global models with compact internal space. The phenomenon, T-dual to brane recombination in the intersecting-brane picture, shares some similarities to small-instanton transitions in non-compact space, though in this case the Abelian magnetic...