The quantum kinetic theory for chiral anomalous fluid has been proposed in 2012 by Prof. WANG Qun and his collaborators J.H.Gao, et al., Physical Review Letters 109, 232301(2012)]. The theory has drawn broad interest in high enegy nuclear physics community. Now he and his collaborators have made another major advance along this direction by derivinga new set of equations: the Covariant Chiral Kinetic Equation (CCKE), which is in close connection with Berry phase structure.

The chiral magnetic effect from chiral anomaly and strong magnetic fields leads to charge separation and local parity violation. /Image by WANG Qun

The work was published in This work has recently been published in Phys. Rev. Lett. 110, 262301(2013) on Jun 24th.
It contains vorticity terms and a 4-dimensional Euclidean Berry monopole which gives axial anomaly. By integrating out the zero-th component of the 4-momentum, the previous 3-dimensional results derived from the Hamiltonian approach can be reproduced, together with the newly derived vorticity terms. The CCKE can be used to simulate the evolution of a chiral anomalous quantum system via probability approach such as Monte-Carlo method.

The Berry phase is a topological phase factor acquired by an eigen-energy state when it undergoes adiabatic evolution along a loop in parameter space. It is in close analogy to the Aharonov-Bohm phase when a charged particle moves in a loop enclosing a magnetic flux, while the Berry curvature is like the magnetic field. The　integral of the Berry curvature over a closed surface can be quantized as integers known as Chern-Simons numbers, which is similar to the Dirac magnetic monopole and has deep connection with the quantum Hall effect. The Berry phase is a beautiful, simple and universal structure in quantum physics and has many interesting applications.
It is well known that extremely strong magnetic fields can be generated in high energy heavy ion collisions, which is the strongest that can be ever made on the earth. The strong magnetic field can lead to many interesting phenomena. The chiral magnetic effect is one of such phenomena and arises from chiral anomaly in high temperature. The chiral magnetic effect can lead to charge separation along the direction of the magnetic field. The chiral vortical effect is an associated effect, which is related to the local rotation of a fluid cell. The chiral vortical effect can lead to the local polarization of hadrons.
These advances in the quantum kinetic theory provide a unified interpretation of the chiral magnetic and vortical effects, chiral anomaly, Berry curvature, and the Berry monopole the framework of Wigner functions.
The work was the result of a joint effect with Prof. CHEN Jiunn-wei of National Taiwan University, Prof. WANG Xinnian of Lawrence-Berkeley National Lab, and Dr. PU Shi, a former member of Prof. WANG Qun's group and now a postdoc at National Taiwan University.