Related Experiment Video
Updated: Mar 12, 2026

Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Effective Action Approach to Bose-Einstein Condensation of Ideal Gases
1University of Leipzig, Institute of Theoretical Physics, Augustusplatz 10, 04109 Leipzig, Germany.
Abstract:
We present a short review of how the effective action formalism, well known in relativistic quantum field theory, can be used to discuss Bose-Einstein condensation of non-relativistic gases. This method lends itself very naturally to an interpretation of Bose-Einstein condensation in terms of symmetry breaking. It also allows for the definition of a very elegant regularization technique involving generalized ζ-functions. We show how this method can be used to recover the well known results for the free boson gas, as well as the charged boson gas in a constant magnetic field. A general criterion for interpreting Bose-Einstein condensation in terms of a phase transition with symmetry breaking is given. Finally we present an analysis of Bose-Einstein condensation in a harmonic oscillator confining potential trap, and show how the results of this simple model are in excellent agreement with experiment.
Related Concept Videos
Deviation from Ideal Behaviour
Kinetic Theory of an Ideal Gas
The number of molecules in one mole is called...
Ideal Gas Equation
Real Gases: Effects of Intermolecular Forces and Molecular Volume Deriving Van der Waals Equation
Van der Waals Equation
First, the attractive forces between molecules, which are stronger at higher densities and reduce the pressure, are considered by adding to the pressure a term equal to the square of the molar density multiplied by a positive coefficient a. Second, the volume...
Ideal Solutions or Mixtures

