Wednesday, May 30, 2018 - 09:00 in V2-210/216
Taking into account the polarized Dirac sea: the nonlinear Euler-Heisenberg model
A talk in the Keine Reihe series by
Eric Séré from Université Paris-Dauphine
| Abstract: |
This is joint work with Philippe Gravejat and Mathieu Lewin (J. Math. Pures Appl., in press). The Euler-Heisenberg model provides a nonlinear system of equations for the electromagnetic field. The nonlinearity takes into account the interaction between the classical electromagnetic field and the Dirac sea. It depends on a small coupling parameter and one recovers the linear Maxwell equations when this parameter is set to zero. In most situations the linear (Maxwell) approximation is extremely accurate, but nonlinear effects cannot be neglected in very strong fields, as for instance on the surface of some neutron stars called «magnetars». We give the first rigorous derivation of the Euler-Heisenberg magnetic energy in the semi-classical limit of slowly varying, time-independent, magnetic fields. The question of (slowly) time-varying fields
remains open.
|
Back
