Toward the quantitative theory of the instanton liquid (I). Phenomenology and the method of collective coordinates

This paper is the first in a series applying the method of collective coordinates to the description of an ensemble of interacting topological fluctuations, the so-called instanton liquid. We first present the results of the semiclassical theory of instantons and then proceed to a summary of known phenomenological facts, both coming from real experiments (for QCD) and from the lattice data. Then we describe the main ideas of the collective coordinate method.