Dark memories in the provincial words of Ingmar Bergman's Fanny and Alexander and Federico Fellini's Amarcord

Dark memories in the provincial words of Ingmar Bergman's Fanny and Alexander and Federico Fellini's AmarcordThis article about Federico Fellini’s Amarcord (1973) and Ingmar Bergman’s Fanny and Alexander (1982) concerns one aspect of the directors’ childhood memories, namely how authoritarian institutions are used to disrupt otherwise fairly idyllic and nostalgic lives and worlds. The films blend detailed memories with playful fantasies, combine experiences of the directors’ alter egos, Titta and Alexander, with rituals of family and larger communities in the provincial cities of Rimini and Uppsala. In each film, bitter memories are given a central role. This article explores the similarities of these bitter memories, as they are imagined in the mature auteurs’ last exceptionally successful films

Propagation of Partially Coherent Photons in an Ultra-Intense Radiation Gas

The scattering of photons off photons at the one-loop level is investigated. We give a short review of the weak field limit, as given by the first order term in the series expansion of the Heisenberg-Euler Lagrangian. The dispersion relation for a photon in a radiation gas is presented. Based on this, a wave kinetic equation and a set of fluid equations is formulated. These equations describe the interaction between a partially coherent electromagnetic pulse and an intense radiation gas. The implications of the results are discussed.Comment: 10 pages, 1 figure, revtex

Photon acceleration in vacuum

A new process associated with the nonlinear optical properties of the electromagnetic vacuum, as predicted by quantum electrodynamics, is described. This can be called photon acceleration in vacuum, and corresponds to the frequency shift that takes place when a given test photon interacts with an intense beam of background radiation.Comment: 10 pages, 2 figures, version to appear in Phys. Lett.

Radiation dominated particle and plasma dynamics

We consider the general problem of charged particle motion in a strong electromagnetic field of arbitrary configuration and find a universal behaviour: for sufficiently high field strengths, the radiation losses lead to a general tendency of the charge to move along the direction that locally yields zero lateral acceleration. The relativistic motion along such a direction results in no radiation losses, according to both classical and quantum descriptions of radiation reaction. We show that such a radiation-free direction (RFD) exists at each point of an arbitrary electromagnetic field, while the time-scale of approaching this direction decreases with the increase of field strength. Thus, in the case of a sufficiently strong electromagnetic field, at each point of space, the charges mainly move and form currents along local RFD, while the deviation of their motion from RFD can be calculated in order to account for their incoherent emission. This forms a general description of particle, and therefore plasma, dynamics in strong electromagnetic fields, the latter can be generated by state-of-the-art lasers or in astrophysical environments

Spin quantum plasmas - new aspects of collective dynamics

Quantum plasmas is a rapidly expanding field of research, with applications ranging from nanoelectronics, nanoscale devices and ultracold plasmas, to inertial confinement fusion and astrophysics. Here we give a short systematic overview of quantum plasmas. In particular, we analyze the collective effects due to spin using fluid models. The introduction of an intrinsic magnetization due to the plasma electron (or positron) spin properties in the magnetohydrodynamic limit is discussed. Finally, a discussion of the theory and examples of applications is given.Comment: 17 pages, short review concerning quantum plasmas, to appear in the Proceedings of the 2007 ICTP Summer College on Plasma Physics, Trieste 30 July - 24 August, 200

Photon gas dynamics in the early universe

Quantum electrodynamics predicts that photons undergo one-loop scattering. The combined effect of this on the behaviour of a photon gas for temperatures above 10^{10} K results in a softening of the equation of state. We calculate the effect this has on the effective equation of state in the early universe, taking into account all the species of the Standard Model. The change to the dynamics of the early universe is discussed.Comment: 4 pages, version to appear in Physics Letters