Lattice QCD: topological charge

[Bobhawke]

I am reading a paper right now on lattice QCD that presents a "method that improves the cooling method and constructs an improved topological charge operator based on the product of link variables forming rectangular Wilson loops."

Unfortunately I am understanding very little of it. It seems like I need some pre-requisite knowledge. The paper makes reference to things like: topological charge, instantons, axial anomalies, etc

I was wondering if someone could point to a resource which could help me understand these concepts

 

[xepma]

A book I happen to now on the subject related to this is: Topological Solitons by Manton and Sutcliffe. But I don't know how it relates to QCD.

 

[humanino]

Lectures on Quantum Chromodynamics by Smilga for instance.

 

[Bobhawke]

Thank you!