Chiral magnetic effect and cosmic magnetic fields

par Oleg Ruchayskiy (École Polytechnique Fédérale de Lausanne)

jeudi 5 déc. 2013, 11:00 → 12:00 Europe/Paris

Auditorium (Annecy-le-Vieux)

It is generally believed that primordial plasma l at high temperatures is homogeneous and isotropic. This assumption underlies the description of many important processes in the early Universe. I will demonstrate that at non-zero values of baryon and lepton number a translationally invariant and homogeneous state of primordial plasma becomes unstable and the system transits towards a ground state, containing a large-scale magnetic fields. The origin of this effect is the chiral anomaly (violations of classical symmetries by quantum effects). I will argue that due to the same phenomenon a new degree of freedom should be added to the magnetohydrodynamic equations, governing the evolution of magnetic fields in relativistic plasma. The resulting "chiral" MHD greatly improves the survival forecast of cosmic magnetic fields generated at or prior to electroweak epoch.

Slides lapth-ruchayskiy.pdf