2019/07/31 by Åsmund Folkestad, Sašo Grozdanov, Krishna Rajagopal +1 · 2 citations
Physics and Astronomy · #Baryon #Baryon number #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Coupling (piping) #Coupling constant #Gauge theory #Gravitation #High-Energy Particle Collisions Research #Particle physics #Physics #Quantum chromodynamics #Quantum electrodynamics #Quantum mechanics #Quark–gluon plasma #hep-ph #hep-th #nucl-ex #nucl-th
paper · pdf · doi:10.1007/jhep12(2019)093
published as JHEP 1912 (2019) 093 · v2: 40 pages, 12 figures. Minor adjustments. Version appearing in JHEP
openalex publication_date 2019/12/01 · arxiv created 2019/12/24 · arxiv updated 2019/12/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
A bstract Sufficiently energetic collisions of heavy ions result in the formation of a droplet of a strongly coupled liquid state of QCD matter known as quark-gluon plasma. By using gauge-gravity duality (holography), a model of a rapidly hydrodynamizing and thermal- izing process like this can be constructed by colliding sheets of energy density moving at the speed of light and tracking the subsequent evolution. In this work, we consider the dual gravitational description of such collisions in the most general bulk theory with a four-derivative gravitational action containing a dynamical metric and a gauge field in five dimensions. Introducing the bulk gauge field enables the analysis of collisions of sheets which carry nonzero “baryon” number density in addition to energy density. Introducing the four-derivative terms enables consideration of such collisions in a gauge theory with finite gauge coupling, working perturbatively in the inverse coupling. While the dynamics of energy and momentum in the presence of perturbative inverse-coupling corrections has been analyzed previously, here we are able to determine the effect of such finite coupling corrections on the dynamics of the density of a conserved global charge, which we take as a model for the dynamics of nonzero baryon number density. In accordance with expec- tations, as the coupling is reduced we observe that after the collisions less baryon density ends up stopped at mid-rapidity and more of it ends up moving near the lightcone.