Research Fellows Directory
Jorge Casalderrey Solana
Dr Jorge Casalderrey Solana
University of Oxford
Micro-seconds after the Big Bang, all matter in the universe was in an exotic state called the Quark Gluon Plasma. The properties of this high-temperature phase are very different from those of ordinary matter. In this phase, the charge of the Strong Force, which at everyday temperatures is confined within protons and neutrons, becomes apparent. Nowadays, this state of matter only exists for a very short time in the debris of the collisions of large heavy ions at the ultra-relativistic energies achieved at the LHC and at RHIC. These accelerators allow us to study the behaviour of that phase right above the transition, where the quarks and gluons that form protons and nucleons interact strongly. In this regime, the interactions of those fundamental particles are so strong that the system cannot be understood as a collection of interacting particles but rather as a strongly coupled liquid with very small viscosity and with no well defined particle-like excitations. The latter is a feature shared by some other unusual materials in nature with interesting properties such as some types of high temperature superconductors. To understand the properties of the strongly coupled plasma created in those collision, I employ holography. This is a tool that relates the type of theories that describe the strong force to gravity in the limit in which interactions become strong. More concretely, my project studies how very energetic spays of particles created in the same heavy ion collisions that form a plasma can be used to determine the properties of this interesting state of matter. These jets of particles are tomographic probes of the system, with which we can understand how the plasma behaves. By studying the high temperature phase of the Strong Force we learn how this fundamental force of Nature works. But in addition, we also learn how the early universe behaved and how the dynamics of strongly coupled systems work.
Interests and expertise (Subject groups)