2016/05/30 by Robert Moerman, R. W. Moerman, Moerman, R. W. +2 · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th) #High-Energy Particle Collisions Research #Nuclear Theory (nucl-th) #Quantum Chromodynamics and Particle Interactions #hep-ph #hep-th #nucl-th
paper · pdf · doi:10.48550/arxiv.1605.09285
36 pages, 7 figures
arxiv created 2016/05/30 · openalex publication_date 2016/05/30 · arxiv updated 2016/05/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We compute the average squared distance, s2(t), travelled by a light-flavour off-mass-shell coloured parton in a strongly-coupled N=4 SU(Nc) super-symmetric Yang Mills plasma using the gauge/string duality. In fact, we derive a closed integral expression for s2(t;a) in AdS3-Schwarzschild, which interpolates between a heavy quark when a = 0 and a light quark when a = 1, that we evaluate analytically for small virtualities - labelled ssmall2(t;a). For arbitrary virtualities, we show that for asymptotically early times the motion is ballistic, .s2(t;a)|t≪β∼ t2, while at asymptotically late times the motion is diffusive, . s2(t;a) |t≫β = ssmall2(t;a) ∼ 2D(a) t, from which we are able to extract the diffusion coefficient D(a). Motivated by the apparent universality of the late time behaviour, we compute ssmall2(t;a,d) and D(a,d) for an arbitrary AdSd-Schwarzschild geometry. From D(a,d) we then compute for the first time the dynamic, time-dependent transverse momentum squared per unit path length picked up by a high momentum light quark in a strongly-coupled plasma, the transport coefficient q(t), which is critically important for phenomenology in heavy ion collisions.