Relativistic Quantum Transport Theory

Abstract

Relativistic quantum transport theory has begun to play an important role in the space-time description of matter under extreme conditions of high energy density in out-of-equilibrium situations. The following introductory lectures on some of its basic concepts and methods comprise the sections: 1. Introduction; 2. Aims of transport theory (classical); 3. Quantum mechanical distribution functions - the density matrix and the Wigner function; 4. Transport theory for quantum fields; 5. Particle production by classical fields; 6. Fluid dynamics of relativistic quantum dust.Comment: Lectures presented at PASI "New States of Matter in Hadronic Interactions", Campos do Jordao, Brazil, Jan.7-18, 2002. - 19 pages; LaTe

The Minimal Modal Interpretation of Quantum Theory

“…According to our interpretation of quantum theory, the final density matrices of the subject system Q and of the measurement apparatus A, obtained by appropriately partial-tracing (38) the composite final state appearing in (104), are respectively given in their diagonal form by…”

Pair Production from Asymmetric Head-on Laser Collisions

“…Conversion of MeV photons to pairs in a background field is described by the established perturbative O(α/π) expression for the total yield (summed over spins) [5,6]…”

“…Prior work has noted that induced pair production requires non-perturbative treatment to account for the many-photon process [12][13][14]. We have solved this challenge with a technique inspired by light-cone formalism: While the pulse collision can be studied in any frame, choosing the CM frame of highly asymmetric colliding pulses makes visible the dominant mechanism for the induced pair production-pair conversion of MeV-energy photons on an external field-and allows computation of the yield using available perturbative expressions [5,6]. The boost into and out of the CM frame produces a relativistic mirror effect and pairs are seen in the lab with energies corresponding to the squared boost factor.…”