VIRIAL COEFFICIENTS FROM (2 + 1)-DIMENSIONAL QED EFFECTIVE ACTIONS AT FINITE TEMPERATURE AND DENSITY

QED effective action at finite temperature and density.

The QED effective action at finite temperature and density is calculated to all orders in an external homogeneous and time-independent magnetic field in the weak coupling limit. The free energy, obtained explicitly, exhibit the expected de Haas – van Alphen oscillations. An effective coupling at finite temperature and density is derived in a closed form and is compared with renormalization grou...

Magnetization in (2+1)-dimensional QED at finite temperature and density.

Quantum field theories in lower dimensions have therefore become of increasing interest in recent years. Both systems mentioned above have been modelled by anyons, which are particles or excitations that obey fractional statistics. Anyons can be described in terms of Chern-Simons field theories [1-3]. The literature on 2+1d field theory in general and Chern-Simons field theory in particular is ...

Time Dependent Effective Actions at Finite Temperature ∗

I study derivative expansions of effective actions at finite temperature, illustrating how the standard methods are badly defined at finite temperature. I then show that by setting up the initial conditions at a finite time, these problems are solved. 1.1 Zero temperature I will work with a simple model of two real fields φ and η 1 L[φ, η] = 1 2 η∆ −1 η − 1 2 gφη 2 + L 0 [φ], (1) and integratin...

Comment on "Anomaly-induced magnetic screening in (2+1)-dimensional QED at finite density"

Anomaly-induced magnetic screening in (2+1) dimensional QED at finite density.

We show that in 2+1 dimensional Quantum Electrodynamics an external magnetic field applied to a finite density of massless fermions is screened, due to a 2 + 1dimensional realization of the underlying 2-dimensional axial anomaly of the space components of the electric current. This is shown to imply screening of the magnetic field, i.e., the Meissner effect. We discuss the physical implications...