2026/01/09(Fri) 11:00 -12:00 五樓第一會議室 5F, 1st Meeting Room
Title
Transport Phenomena in Strongly Magnetized Relativistic Matter
Speaker
Dr. Ritesh Gosh (Institute of Physics, Academia Sinica)Abstract
We investigate transport coefficients in hot, strongly magnetized plasma using first-principles quantum field-theoretical methods. While such coefficients are often computed using kinetic theory, this approach becomes inadequate in quantizing magnetic fields, where the transverse motion of charged particles is discretized into Landau levels (n=0,1,2,…). In this regime, transport properties must instead be derived directly from quantum field theory.
Using Kubo’s linear response formalism, we express the electrical conductivity tensor in terms of fermion damping rates in the Landau-level representation. Employing recent leading-order results for these damping rates, we obtain analytical expressions for both longitudinal and transverse conductivities. Our findings reveal distinct mechanisms responsible for the strong anisotropy of charge transport in a magnetic field: the longitudinal conductivity is enhanced, whereas the transverse conductivity is strongly suppressed. This reflects the fundamental constraint that charged particles move freely along the magnetic field but experience restricted motion perpendicular to it due to the phenomenon of Landau quantization. At zero magnetic field, longitudinal transport is governed by the probability of charge carriers remaining undamped, while transverse transport requires quantum transitions between Landau levels to overcome localization in Landau orbits.
We also extend our investigation to the shear and bulk viscosities of strongly magnetized relativistic plasmas and demonstrate the inherently anisotropic nature of these viscous coefficients in a strong magnetic field. Finally, we discuss the physical implications of these magneto-transport coefficients in the context of magnetar physics and the strongly magnetized quark-gluon plasma produced in heavy-ion collisions.
Language
演講語言 (Language): in English