In this figure
one axis is the temperature (this one is no problem), the other one is the baryon chemical potential which causes my confusion.
Figure from here: Phase diagram of simplified QCD.
The text I'm referring to (with a similar figure): http://www.fair-center.eu/for-users/experiments/cbm/introduction.html.
Anyway, in a text about phases of QCD, the authors referred to this x-axis as the density and not the baryon chemical potential.
So my questions are:
What is the baryon chemical potential? What does it tell me?
What does it have to do with densities? Is it just a "synonym" for densities?
Also, as far as I understood, the phases aren't like the phases of "normal" matter, e.g. hadronic matter is at 0 K and 300 million tons per cm3 (see the link for the text) in a "liquid" phase. So, what do the phases look like? Why is it "liquid" and not liquid?
Thanks in advance!