2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/47224The catalysis of chiral symmetry breaking by a magnetic field in the massless weak-coupling phase of QED is studied. The dynamical mass of a fermion (energy gap in the fermion spectrum) is shown to depend essentially nonanalytically on the renormalized coupling constant $α$ in a strong magnetic field. The temperature of the symmetry restoration is calculated analytically as $T_c\approx m_{dyn}$, where $m_{dyn}$ is the dynamical mass of a fermion at zero temperature.12 pages, Latex file. Talk given at the "APCTP-ICTP Joint International Conference on Recent Developments in Non-perturbative Methods" held on May 26-30, 1997 at Seoul, KoreaHigh Energy Physics - Phenomenologytext