Abstract: Relativistic heavy-ion experiments at Brookhaven National Laboratory have successfully reproduced the Quark Gluon Plasma in the laboratory, which is the smallest fluid known to humankind.  The QGP acts as a nearly perfect fluid whose flow fluctuations are extremely well described by event-by-event relativistic viscous hydrodynamics.   Additionally, the QGP can be scanned by particles produced in the early stages after the collision such as high pT particles. There is an enhancement of the flow fluctuations at high pT, which indicates the importance of energy loss fluctuations in a strongly interacting medium.  Recently, dilepton studies have gained attention since these particles allow one to scan different parts of the QGP evolution.  Here we use the state of the art IP-Glasma+MUSIC model to analyze their dilepton flow fluctuations where we find there is a suppression in the fluctuations, in contrast to both the soft and hard sectors associated with light hadrons.

Abstract: Examples for hydrodynamic collective modes are sound waves, shear and diffusive modes. But what are non-hydrodynamic collective modes? Most physicists likely have never ever heard about non-hydrodynamic modes in their entire career. Indeed, there does not seem to be a single textbook on this topic. This seminar will give an introduction to the physics of non-hydrodynamic modes, featuring gravitational waves, string theory predictions for experiment, cold atoms close to unitarity and heavy-ion collisions.

Abstract: This talk aims to give an accessible introduction and overview of employing holography to better understand the creation of quark-gluon plasma in heavy ion collisions. Holography is a framework, originating from string theory, where it was realised that the dynamics of temperature and entropy present on black hole horizons is precisely described by certain infinitely strongly interacting quantum field theories. We will apply this framework in a setting where a black hole forms from two colliding `holographic nuclei’, and show that the resulting plasma is very quickly described by viscous relativistic hydrodynamics, a process now called hydrodynamisation. Lastly, we give some updates on recent extensions to Einstein-Gauss-Bonnet gravity, which can mimic quantum field theories with a finite coupling constant.